Method of manufacturing polyelectrolyte

ABSTRACT

A method of manufacturing a polyelectrolyte having the step of sulfonating polystyrene resin in a state where the polystyrene resin has been dissolved or dispersed in solvent composed of alicyclic compounds.

CROSS REFERENCE OF RELATED APPLICATIONS

This application claims priority to, and benefit from, U.S. patentapplication Ser. No. 08/889,011, filed Jul. 7, 1997, now issued as U.S.Pat. No. 6,022,928, which claims priority to JP 08-177815, filed Jul. 8,1996, JP 09-256982, filed Sep. 27, 1996, JP 08-256984, filed Sep. 27,1996, JP 09-262041, filed Oct. 2, 1996, JP 08-262039, filed Oct. 2,1996, JP 09-000372, filed Jan. 6, 1997, and JP 09-001650, filed Jan. 8,1997, the disclosures of which are entirely incorporated by referenceherein.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a method of manufacturing apolyelectrolyte such that ion groups are introduced into polystyreneresin.

2. Description of Prior Art

Polystyrene resin has excellent electric characteristic, satisfactoryrigidity and sufficient water resistance while exhibiting low costs.Therefore, the polystyrene resin is solely or formed into an alloycombined with a copolymer or another resin so as to be used in buffers(foamable styrol), packing materials, electric products and frames andvarious parts for automobiles. Thus, the polystyrene resin is ageneral-purpose resin considered equal to polyolefin resin representedby polyethylene.

In addition to the purpose of the polystyrene resin for use as thestructural material, the polystyrene resin is refined into apolyelectrolyte so as to be used as coagulant for waste water treatment,an additive for cement, a material for fluidizing coal slurry,dispersant for inorganic pigment, a material for reinforcing paper, asurface sizing material for paper, a conductive material for anelectronic copying machine, a destaticizer, a scale preventive material,dispersant for emulsion polymerization and aqueous glue and the like.

To refine the polystyrene resin into a polyelectrolyte, for example, amethod may be employed in which sulfonate or an amine salt subjected toa chloromethylation process is introduced into the polystyrene resin sothat the polystyrene resin is formed into a water-soluble polymer.

However, an actual process for refining the polystyrene resin into apolyelectrolyte encounters a variety of problems.

For example, sulfonation of the polystyrene resin, which is performed ina sulfonating agent, requires a large quantity of the sulfonating agent,represented by concentrated sulfuric acid. Moreover, the largequantities of the sulfonating agent and water for cleaning thesulfonating agent are discharged after the reactions have beenperformed. Thus, there arises a problem in that resources cannot besaved, the waste cannot be reduced and the manufacturing cost cannot bereduced. If the sulfonating operation is performed as described above,molecule crosslinking (sulfon crosslinking) easily occur when reactionsare performed. Thus, the polymers are allowed to gel and thereforeunnecessary polymers can easily be formed in water. Moreover, theforegoing gelation becomes apparent in proportion to the molecularweight of the polymer and the molecule chains of the polymers can easilybe cut. Therefore, a high molecular polyelectrolyte cannot easily beobtained.

When the sulfonating reactions are performed in a chlorine solvent, alarge quantity of the chlorine solvent remains in the polyelectrolyteafter subjected to the reactions and its water solution. As a result,halogen compounds are contained in the polyelectrolyte product.Therefore, if the foregoing polyelectrolyte is used in the coagulant forwaste water treatment, dispersant for cement, absorbing resin, a surfacesizing material for paper or the like, the halogen compounds aredischarged into waste water. Thus, the foregoing polyelectrolyte cannotpractically be employed because of difficulty to satisfy a waste waterregulation.

Since the molecular weight (Mw) of the thus obtained polyelectrolyte isgenerally 150,000 to 600,000, a polyelectrolyte having a large molecularweight has been required to improve the performance when thepolyelectrolyte is used as, for example, a coagulant.

Since the sulfonating reaction encounters reduction in the reaction rateif water is contained in the system, water must completely be removed toagain use the solvent in the reactions.

However, a conventional technique, for example, still standingseparation, involves a fact that sulfonated substances of aromaticpolymers, which are reaction products, serve as surface active agents.Thus, the boundary between the aqueous layer and the solvent layerbecomes confused, thus causing the separation to be made difficult. Whenthe solvent is recovered by distillation, the solvent of the chlorinetype hydrocarbon and water form azeotropic mixture. Complete removal ofwater from the solvent cannot easily be realized, thus causing anecessity for performing refining and dehydration processes to arise.

Therefore, there arises problems in that the working efficiencydeteriorates and new additional facility is required.

What is worse, the polystyrene resin has a problem of a halogen flameretardant.

Since the halogen flame retardant has a significant flame retardanteffect with respect to a variety of plastic materials and its cost isvery low, the halogen flame retardant is used widely over the world.

However, use of the halogen flame retardant raises a problem because thehalogen flame retardant generates halogenated hydrogen when it burns. Inparticular, use of decabromodiphenyl oxide (DBDPO), which is used mostwidely and which generates toxic substances, such as dioxine, has beenregulated.

The halogen flame retardant, having excellent flame retardant effectwith respect to aromatic resins represented by styrene resin, are widelyused in the frames of home electronic products and as a material ofparts.

Therefore, if the home electronic products are dumped, a large quantityof plastic substances containing the halogen flame retardant aredischarged.

The plastic wastes are usually burnt or reclaimed except for a smallportion which is recycled by heating and melting.

When the plastic wastes are attempted to be disposed by burning, theabove-mentioned problem of generation of toxic gases arises. Therefore,the disposal must be performed by the reclamation at present.

The amount of plastic wastes containing the halogen flame retardant hasbeen enlarged year by year. Therefore, the reclamation disposal isineffective and thus there arises a critical problem for Japanconsiderably wanting of reclamation plants.

If recycling of plastic wastes is attempted, recycle of the plasticcontaining the halogen flame retardant, the use of which is regulated,is not preferable.

OBJECTS AND SUMMARY OF THE INVENTION

An object of the present invention is to provide a method ofmanufacturing a polyelectrolyte capable of manufacturing apolyelectrolyte containing no halogen compound while preventingdischarge of a large quantity of toxic wastes.

Another object of the present invention is to provide a method ofmanufacturing a water-soluble polyelectrolyte having larger molecularweight.

An object of the present invention is to enable a solvent used in asulfonating reaction of aromatic polymers to be recovered in a statewhere no water is contained and to form an efficient sulfonating systemby recycling the solvent.

Another object of the present invention is to provide a processingmethod capable of efficiently separating halogen flame retardantcontaining plastic waste or the like.

According to one aspect of the present invention, there is provided amethod of manufacturing a polyelectrolyte comprising the step ofsulfonating polystyrene resin in a state where the polystyrene resin isdissolved or dispersed in a solvent composed of an alicyclic compound.

When the alicyclic compound is employed as the solvent in the processfor sulfonating the polystyrene resin, gelation can be prevented. Sincethe necessity of using a halogen compound as the solvent can be removed,a polyelectrolyte containing no halogen compound can be manufacturedwithout discharge of a large quantity of toxic wastes.

According to a second aspect of the present invention, there is provideda method of manufacturing a polyelectrolyte comprising the steps ofintroducing ion groups into copolymers of styrene and conjugate diene;and crosslinking and/or polymerizing the conjugate diene in thecopolymer so that refining to a water-soluble polyelectrolyte isperformed.

When the conjugate diene is previously contained in the polystyreneresin and the conjugate diene units are crosslinked and/or polymerized,the water-soluble polyelectrolyte having a large molecular weight can beobtained.

A third aspect of the present invention is characterized in thataromatic polymers are added to and dissolved in solvent suppliedcontinuously; sulfonating agents are supplied to the solution to performsulfonating reactions; generated reaction products and the solvents areseparated from each other; and the separated solvents are returned so asto be again used in the sulfonating reactions.

In the above-mentioned aspect, the sulfonated aromatic polymers areformed into solid matters so as to be separated from the solvents.Therefore, the necessity of adding water to the reaction system can beremoved.

Therefore, the separated solvents do not contain water and thus thesolvents can be recycled.

A fourth aspect of the present invention is characterized in thatplastics containing halogen flame retardants are subjected to an acidprocess in an organic solvent; ion groups are introduced into resincomponents to form water-soluble polymer; and then the halogen flameretardants in the organic solvent are separated.

When the plastics containing the halogen flame retardants are subjectedto the acid process in the organic solvents, the ion groups areintroduced into the resin components so as to be formed intowater-soluble polymers so that the phase is shifted to an aqueous phase.

On the other hand, the above-mentioned introduction of the ion groupsdoes not take place in the halogen flame retardants. Thus, the halogenflame retardants are, in the non-reacted state, retained to be theorganic solvent phase.

Therefore, separation of the aqueous phase and the organic solvent phasefrom each other causes the resin components and the halogen flameretardants to quickly be separated from each other.

Other objects, features and advantages of the invention will be evidentfrom the following detailed description of the preferred embodimentsdescribed in conjunction with the attached drawings.

BRIEF DESCRIPTION OF THE PREFERRED EMBODIMENTS

FIG. 1 is a flow chart showing a process for sulfonating aromaticpolymers;

FIG. 2 is a schematic view showing an example of a solid-liquidseparator; and

FIG. 3 is a schematic view showing another example of a solid-liquidseparator.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

A method of manufacturing a polyelectrolyte according to the presentinvention is structured such that polystyrene resin is sulfonated in astate where the polystyrene resin is dissolved or dispersed in a solventcomposed of alicyclic compounds.

The alicyclic compound may be any one of the following materials:cycloparrafin, such as cyclopentane, methylcyclopentane, cyclohexane,methylcyclohexane, ethylcyclohexane, p-menthane, bicyclohexyl, decalinor sabinane; and cycloolefin, such as cyclohexene, monocyclicmonoterpene (limonene, sylvestrene, terpinen or terpinolene), dicyclicmonoterpene (carene, pinene, sabinene or camphene). In particular, it ispreferable that cycloparrafin be employed, more preferably cyclohexaneor its derivative. Note that the above-mentioned compound may beemployed solely or a plurality of the compounds may be combined.

Solvent which can be mixed with the foregoing alicyclic compounds areexemplified by paraffin type hydrocarbon having one to seven carbonatoms, acetonitrile, carbon disulfide, tetrahydrofuran,tetrahydropyrane, 1,2-dimethoxyethane, acetone, methylethylketone andthiophene. In particular, it is preferable that the paraffin typehydrocarbon having one to seven carbon atoms, acetonitrile,tetrahydrofuran or acetone be employed. Although the mixture ratio isnot limited when the selected solvent is mixed with the alicycliccompound, it is preferable that the ratio be 1% to 100% of the volume ofthe alicyclic compound.

Note that the solvent once used in the sulfonating process may berecovered by a method such as extraction or distillation so as to beagain used in the sulfonating process. However, it is preferable thatthe recovery of the solvent be performed prior to adding the chlorinecompound or its water solution to the reaction system. If a solvent of atype in which the chlorine compound and water retain is used in thesulfonating process, the sulfonating reaction is prevented.

The polystyrene resin which is dissolved or dispersed in theabove-mentioned solvent may be composed solely of polystyrene or acopolymer of styrene and another monomer. If the polystyrene resin is inthe form of the copolymer, it is preferable that the content of thecopolymer be 30 mol % or larger of the overall volume. The foregoingpolystyrene resin may be an alloy or blend with another polymer. In thiscase, it is preferable that the polystyrene resin be contained by 20 wt% or more of the overall weight of the resin.

The styrene type copolymer is exemplified by styrene-butadiene,styrene-acrylonitrile, styrene-butadiene-acrylonitrile, styrene-(metha)acrylic acid, styrene-(metha) acrylic acid ester (aliphatic hydrocarbonhaving one to four carbon atoms), styrene-acrylonitrile-(metha) acrylicacid ester (aliphatic hydrocarbon having one to four carbon atoms),styrene-butadiene-(metha) acrylic acid ester (aliphatic hydrocarbonhaving one to four carbon atoms), styrene-maleic anhydride andstyrene-itaconic anhydride. Among the foregoing styrene copolymers, itis preferable to employ any one of styrene-butadiene,styrene-acrylonitrile, styrene-butadiene-acrylonitrile,styrene-acrylonitrile-(metha) acrylic acid ester (aliphatic hydrocarbonhaving one to four carbon atoms), styrene-butadiene-(metha) acrylic acidester (aliphatic hydrocarbon having one to four carbon atoms) andstyrene-maleic anhydride. The styrene type copolymer may be employedsolely or used together with polystyrene or another styrene typecopolymer. The molecular weight of the polystyrene resin is 5,000 to10,000,000, preferably 50,000 to 1,000,000 and most preferably 100,000to 500,000.

When the above-mentioned polystyrene resin and another polymer arealloyed or blended, the polymer is exemplified by polyphenylene ether,polycarbonate, polyphenylene sulfide, polyamide (Nylon), polyethyleneterephthalate and polybutylene terephthalate. Among the foregoingpolymers, it is preferable that polyphenylene ether or polycarbonate beemployed. Any one of the foregoing polymers may be employed solely ortheir combination may be employed.

The foregoing types of polystyrene resin may be employed: polystyreneresin (a virgin material) prepared newly for manufacturing thepolyelectrolyte according to the present invention or a refuse (a waste)from a plant, a retail shop, a home or the like. Virgin materials andwastes may be used together. The polystyrene resin may be formed intopellet, powder or rod shape, a molded shape, a foamed shape or granular,fiber or film shape.

Since the present invention enables the polystyrene resin productsmass-produced as the general-purpose resins to be recycled as describedabove, a significant advantage can be realized in view of protection ofthe global atmosphere. In the foregoing viewpoint, it is preferable thatthe polystyrene resin be wastes rather than the virgin materials. Notethat it is preferable that wastes recovered from plants or retail shopsbe employed because these wastes have relatively uniform compositions ascompared with those recovered from homes.

The sulfonating process may be performed such that the polystyrene resinis previously dissolved or dispersed in the solvent and then thesulfonating agent is added. When the polystyrene resin and anotherpolymer are used together, the two materials are dissolved or dispersedin the organic solvent. Note that the sulfonating reaction can beperformed uniformly if the foregoing resins are dissolved in the solventas compared with a method in which the resins are dispersed in thesolvent. The concentration of the resin in the sulfonating reactionsystem is made to be 0.05 wt % to 30 wt %, preferably 0.2 wt % to 10 wt%. If the concentration is too low, the manufacturing efficiency and arate for introducing sulfon group into the polymer are lowered. If theconcentration is too high, the quantities of gelled products andunreacted substances are unintentionally enlarged.

The sulfonating agent is exemplified by sulfuric anhydride, fumingsulfuric acid, chlorosulfonic acid and concentrated sulphuric acid. Thequantity of the sulfonating agent to be added is 0.5 mol to 2.0 mol perone mol of a benzene ring of the side chains contained in thepolystyrene resin, preferably 0.7 mol to 1.5 mol. If polyphenylene etheror polycarbonate resin is used together, the quantity of the sulfonatingagent is determined such that the benzene rings of the main chains inthe resin and the benzene rings in the polystyrene resin are added. Ifthe quantity of the added sulfonating agent is too small, the degree ofsulfonation becomes insufficient and thus the solubility with respect towater deteriorates. If the quantity is too large, crosslinking in amolecule and between molecules easily occurs. As a result, by-productsincrease, thus unintentionally deteriorating the solubility with respectto water.

The addition of the sulfonating agent may be performed by dropping thesulfonating agent into a solution in which the polystyrene resin ispreviously dissolved in the alicyclic compound or by dropping thesolution in which the polystyrene resin is dissolved in the alicycliccompound to a solution in which the sulfonating agent is added to thealicyclic compound. The sulfonating agent may be used together with aLewis base. The solution in which the polystyrene resin is dissolved inthe alicyclic compound and the sulfonating agent may simultaneously beadded to a solution of the alicyclic compound to which the Lewis basehas been added.

The Lewis base which is used together with the sulfonating agent isexemplified by alkyl phosphate, such as triethyl phosphate or trimethylphosphate, dioxane, acetic anhydride, ethyl acetate, ethyl palmitate,diethyl ether and thioxane. The quantity of the Lewis base to be addedis 0.01 mol to 2.0 mol per one mol of benzene rings of side chainscontained in the polystyrene resin, preferably 0.02 mol to 1.0 mol. Ifthe polyphenylene ether or the polycarbonate resin is used together, thequantity of the Lewis base to be added is determined such that thebenzene rings of the main chains in the resin and the benzene rings inthe polystyrene resin are added. If the quantity of the added Lewis baseis too small, gelled products can easily be generated in the sulfonatingreactions. If the quantity is too large, the sulfonating reaction cannoteasily proceed. As a result, the yield deteriorates.

The sulfonating reaction is performed at 0° C. to 100° C., preferably30° C. to 80° C. If the temperature is too low, the sulfonating reactioncannot easily proceed.

The time period in which the sulfonating reaction is performed is 10minutes to 10 hours excluding the time period for which the sulfonatingagent is dropped, preferably 30 minutes to 5 hours.

After the sulfonating process has been performed as described above, aneutralizing process is performed to cause the sulfonated material toreact with chlorine compounds. The chlorine compound is exemplified by acompound, such as oxide, hydride, carbonate, acetate, sulfate orphosphate of alkali metal, such as sodium, lithium or calcium or,alkaline earth metal, such as magnesium or calcium; ammonia; and primaryto tertiary alkylamine compounds. The foregoing material is, as it is orin a state of water solution, gradually added to complete theneutralizing process. If the foregoing chlorine compound is added in theform of the water solution, the quantity of water to be added variesdepending upon the molecular weight of the polystyrene resin. Thequantity is made to be 0.5 part by weight to 100 parts by weight whenthe overall quantity of the resin is made to be one part by weight,preferably 1 part by weight to 50 parts by weight. After theneutralizing process has been completed, the solvent is required to beremoved by separation or distillation. To reduce the residual quantityof the solvent, it is preferable that the removal be performed bydistillation as compared with the separation.

As a result, a water-soluble polyelectrolyte containing the inorganicpigment can be obtained. Although dispersion easiness in the watersolution and uniformity in the same can be improved if the inorganicpigment is contained in the polyelectrolyte, the inorganic pigment maybe removed by filtration using a filter, if necessary.

The thus-obtained polyelectrolyte can be used variously as a polymermaterial having no halogen compound contained therein. Thepolyelectrolyte can be used in, for example, coagulant for disposingwaste water, dispersant for cement, absorbing resin, a sizing agent forpaper, a conducting agent for an electronic copying machine, anantistatic agent, ion exchange resin and chelate resin. Among theabove-mentioned purposes, the polyelectrolyte is effective when used inthe dispersant for cement, the absorbing resin or the sizing agent forpaper.

A method of manufacturing the polyelectrolyte will now be describedwhich comprises the steps of introducing ion groups into copolymers ofstyrene and conjugate diene and crosslinking/polymerizing the conjugatediene units in the copolymers will now be described.

By crosslinking and/or polymerizing conjugate diene units in thecopolymers, the molecular weight of the polyelectrolyte can be enlarged.

The polyelectrolyte obtained by the foregoing method may be used ascoagulant for disposing waste water, an additive to cement,superplasticizer for coal slurry, dispersant for inorganic pigment,paper strength enhancer, a surface sizing agent for paper, a conductiveagent for an electronic copying machine, an antistatic agent, a scalepreventive agent, dispersant for emulsion polymerization and aqueousglue. When the molecular weight Mw is made to be 600,000 or larger, theabove-mentioned polyelectrolyte can be used as coagulant for disposingwaste water, absorbing resin, ion exchange resin, chelate resin, paperstrength enhancer, a surface sizing agent for paper and superplasticizerfor coal slurry.

The conjugate diene which is copolymerized with styrene is exemplifiedby butadiene and isoprene. The content of the conjugate diene units inthe copolymer is 0.05 mol % to 20 mol % with respect to all monomerunits, preferably 0.1 mol % to 10 mol %. When the obtainedpolyelectrolyte is used as the coagulant for disposing waste water, thecontent of the conjugate diene units in the copolymer is made to be 0.1mol % to 10 mol % with respect to all monomer units, preferably 0.5 mol% to 5 mol %. If the quantity of the conjugate diene units in thepolystyrene resin is to small, the crosslinking reactions and thepolymerizing reaction do not easily take place in the double bondportions. Thus, the effect of enlarging the molecular weight cannot beobtained. If the quantity of the conjugate diene units is too large, thepolystyrene resin cannot easily be dissolved in the organic solvent andthus uniform reactions cannot easily be performed. Moreover, the degreeof crosslinking and/or polymerization is raised excessively, thuscausing gelled products to be easily generated. As a result,introduction of the ion groups into the resin cannot easily beperformed.

In a viewpoint of causing the characteristics of the sulfonatedpolystyrene to exhibit, the quantity of the styrene units in thepolystyrene resin is made to be 80 mol % or more with respect to allmonomer units, preferably 90 mol % or more.

The polystyrene resin for use in the present invention may contain othermonomers except for the conjugate diene, the other monomers beingexemplified by acrylonitrile, (metha) acrylic acid, (metha) acrylate(aliphatic hydrocarbon having one to four carbon atoms), maleicanhydride, itaconic anhydride and α-methylstyrene.

The molecular weight of the polystyrene resin is made to be 2,000 to2,000,000, preferably 5,000 to 500,000. If the molecular weight is toosmall, the required characteristics as the polyelectrolyte cannot beobtained. If the molecular weight is too large, the solubility into theorganic solvent deteriorates when the sulfonating reactions of thepolystyrene resin are performed in the organic solvent. In this case,reactions are performed nonuniformly.

The above-mentioned polystyrene resin may contain a dye, stabilizer,flame retardant agent, plasticizer, filler and another auxiliaryadditives.

The polystyrene resin (copolymer) may be used solely or in combinationwith polystyrene or another styrene copolymer. It may be alloyed orblended with another polymer. The other polymer which is alloyed orblended as described above is exemplified by polyphenylene ether,polycarbonate, polyphenylene sulfide, polyamide (Nylon), polyethyleneterephthalate and polybutylene terephthalate. The foregoing polymer maybe employed solely or plural types of the polymers may be combined.

If the foregoing type polystyrene resin is employed, polystyrene resin(a virgin material) prepared newly for manufacturing the polyelectrolyteaccording to the present invention or a refuse (a waste) from a plant, aretail shop, a home or the like may be employed. Virgin materials andwastes may be used together. The polystyrene resin may be formed intopellet, powder or rod shape, a molded shape, a foamed shape or granular,fiber or film shape.

Since the present invention enables the polystyrene resin productsmass-produced as the general-purpose resins to be recycled as describedabove, a significant advantage can be realized in view of protection ofthe global atmosphere. In the foregoing viewpoint, it is preferable thatthe polystyrene resin be wastes rather than the virgin materials. Notethat it is preferable that wastes recovered from plants or retail shopsbe employed because these wastes have relatively uniform compositions ascompared with those recovered from homes.

The ion groups which are introduced into the polystyrene resin areexemplified by a material at least selected from a group consisting ofsulfonic acid, its salt, chloromethylated amine salt, carbonic acid, itssalt, PO(OH)₂, its salt, CH₂PO(OH)₂ and its salt.

The ion groups are introduced by, causing the polystyrene resin(copolymer) to react with various oxidizers. For example, when thepolystyrene resin is caused to react with the oxidizers in organicsolvent containing the sulfonating agent represented by sulfuricanhydride, sulfon groups can be introduced. After n-butyl lithium hasbeen added, reaction with dry ice enables carboxyl groups to beintroduced. After phosphorous trichloride has been added, a hydrolysisprocess is performed so that —PO(OH)₂ groups can be introduced. When thechlorine compounds are allowed to react with the above-mentioned acidicgroup, neutral salts of the above-mentioned acidic groups are, as theion groups, introduced.

The polystyrene resin is chloromethylated by chloromethyl ether andLewis acid, and then caused to react with ammonia or various aminecompounds so that chloromethylated tertiary amine salts orchloromethylated quaternary amine salts are introduced. After thechloromethylation has been performed as described above, hydrolysis isperformed by causing the chloromethylated polystyrene resin to reactwith the phosphorous trichloride. Thus, —CH₂PO(OH)₂ groups can beintroduced. If reactions with chlorine compounds are further performed,their neutral salts are introduced as the ion groups.

When the ion groups are introduced as described above, any one of thefollowing reaction solvents is employed: aliphatic halogen hydrocarbonrepresented by 1,2-dichloroethane, chloroform, dichloromethane and1,1-dichloroethane; an alicyclic compound represented by cyclohexane,methylcyclohexane and cyclobenzene; nitromethane; and nitrobenzene. Ifthe alicyclic compound is employed, the polyelectrolyte containing nohalogen compound can be manufactured without discharge of toxic waste.The above-mentioned organic solvent may be used solely or in combinationof a plurality of organic solvents. The mixture ratio is not limitedparticularly.

The above-mentioned organic solvent may be used such that it is mixedwith another solvent. The other solvent which can be used in the mixtureis exemplified by paraffin type hydrocarbon having one to seven carbonatoms, acetonitrile, carbon disulfide, tetrahydrofuran, tetrahydropiran,1,2-dimethoxyethane, acetone, methylethylketone and thiophene. Inparticular, it is preferable that any one of paraffin type hydrocarbonhaving one to seven carbon atoms, acetonitrile, tetrahydrofuran andacetone be employed. In a case where the above-mentioned solvent ismixed with the aliphatic halogen hydrocarbon or the alicyclic compound,the mixture ratio is not limited particularly. It is preferable that thequantity of the solvent be 1% to 100% of the volume of the aliphatichalogen hydrocarbon or the alicyclic compound.

The solvent once used in the introduction reactions of the ion groupscan be recovered by extracting or distillation after the reactions havebeen performed so as to be used again. It is preferable that therecovery of the solvent be performed prior to adding the chlorinecompound or its water solution to the reaction system.

When the reaction for introducing the ion groups is performed by usingthe above-mentioned solvent, the concentration of the polystyrene resinis made to be 0.1 wt % to 30 wt %, preferably 0.5 wt % to 20 wt %. Ifthe concentration is too low, the manufacturing efficiency and a ratefor introducing sulfon group into the polymer are lowered. If theconcentration is too high, the quantities of gelled products andunreacted substances are unintentionally enlarged.

The sulfonating reaction is performed at 0° C. to 100° C., preferably10° C. to 80° C. If the temperature is too low, the reactions cannoteasily proceed and yield deteriorates. The period of time in which thereactions are performed is made to be 10 minutes to 40 hours, preferably30 minutes to 20 hours.

The chlorine compound for use in the neutralization of the ion groups isexemplified by a compound such as oxide, hydride, carbonate, acetate,sulfate or phosphate of alkali metal, such as sodium, lithium orpotassium or alkali earth metal, such as magnesium or calcium; ammonia;primary to tertiary alikylamine compound. The selected material is, asit is, or in the form of water solution, gradually added to that theneutralizing process is completed.

The quantity of the ion groups, which are introduced as described aboveis made to be 20 mol % or more with respect to all monomer units,preferably 40 mol % or more. If the ratio of the introduced ion groupsis lower than the above-mentioned range, a polyelectrolyte havingsufficient water solubility cannot be obtained.

As described above, the ion groups can be introduced into thepolystyrene resin containing the conjugate diene units. In the presentinvention, the conjugate diene units are crosslinked and/or polymerizedto refine the same into an electrolyte having larger molecular weight.

Chemicals for causing the crosslinking reactions and/or polymerizingreactions to take place are exemplified by inorganic or organicperoxide, an azo compound and the like.

Specifically, the inorganic peroxide is exemplified by hydrogen peroxidesolution, peroxosulfuric acid, its salt compound, peroxocarbonate,peroxophosphoric acid, its salt compound, peroxonitric acid, its saltcompound, ozone, perchloric acid, permanganic acid and its salt. Amongthe foregoing materials, it is preferable that any one of the hydrogenperoxide solution, peroxosulfuric acid, its salt compound and ozone beemployed.

The organic peroxide is exemplified by the following materials.

Hydroperoxides: t-butylhydroperoxide, cumenehydroperoxide, diisopropylbenzenehydroperoxide, P-menthane hydroperoxide,2,5-dimethyl-2,5-dihydroperoxy hexane, 2,5-dimethyl-2,5-dihydroperoxyhexyne-3 and pinene hydroperoxide.

Dialkylperoxides: di-t-butylperoxide, di-t-amilperoxide,t-butylcumylperoxide, dicumylperoxide,2,5-dimethyl-2,5-di(t-butylperoxy)hexane,2,5-dimethyl-2,5-di(t-butylperoxy)hexyne-3, α,α′-bis(t-butylperoxy)diisopropyl benzene, 1,2-bis(t-butylperoxy)-3,3,5-trimethyl cyclohexane, n-butyl-4,4-bis(t-butylperoxy)valleriite,2,2-bis(4,4-di-t-butyl)peroxicyclohexyl)propane and2,2-bis(t-butylperoxy)butane, 1,1-di-(t-butylperoxy)cyclohexane.

Diacylperoxides: caprilydeperoxide, lauroyl peroxide, stearoyl peroxide,succinic acid peroxide, benzoyl peroxide, p-chlorobenzoyl peroxide,2,4-dichlorobenzoyl peroxide and the like.

Peroxy esters: t-butylpeorxyacetic acid, t-butylperoxy-2-ethylhexanoate,t-butylperoxylaurate, t-butylperoxybenzoate,di-t-butyldiperoxyphthalate, 2,5-dimethyl-2,5-di(benzoylperoxy)hexane,2,5-dimethyl-2,5-di(benzoylperoxy)hexyne-3, t-butylperoxy maleic acid,t-butylperoxyisopropyl carbonate and the like.

Ketone peroxides: methylethylketoneperoxide, methylisobutylketoneperoxide, cyclohexane peroxide and the like.

The above-mentioned peroxides may be used together with various reducersor crosslinking assistants. The reducers are exemplified by ions ofmetal, such as cobalt, nickel, iron, copper, manganese, selenium orsodium; and amine compounds, such as dimethylaniline. The crosslinkingassistants are exemplified by sulfur, p-quinonedioxime,p,p-dibenzoylquinonedixime, laurylmethacrylate, ethyleneglycol acrylate,triethyleneglycol acrylate, tetraethyleneglycoldimetha acrylate,polyethyleneglycoldimetha acrylate, trimethylolpropenetrimetha acrylate,methylmethacrylate, diarylfumarate, diarylphthalate, tetraaryloxyethane,triarylcyanurate, maleimide, phenylmaleimide,N,N′-m-phenylenehismaleimide, maleic anhydride, itaconic acid,divinylbenzene, vinyltoluene and polybutadiene having small molecularweight (Mw=1,000 to 5,000).

The azo compounds which may by employed as the chemicals for causing thecrosslinking and/or polymerizing reactions to take place are exemplifiedby: azobisbutylonitrile, 1-[(1-cyano-1-methylethyl)azo]formamide,1,1-azobis(cyclohexane-1-carbonitrile),2,2-azobis(2-methylpropionamidine)dihydrochloride,2,2-azobis(2-methylbutylonitrile),2,2-azobis(2,4-dimethylvaleronitrile),2,2-azobis(4-methoxy-2,4-dimethylvaleronitrile), 4,4′-azobis(4-cyanovaleric acid), dimethyl-2,2′-azobis(2-methylpropionate), 2,2′-azobis[2-(2-imidazolyne-2-yl)propane]dihydrochloride, 2,2′-azobis[2-(2-imidazoline-2-yl)propane],2,2′-azobis{2-methyl-N-[1,1-bis(hydroxymethyl)-2-hydroxyethyl]propionamide},2,2′-azobis{2-methyl-N-[1,1-bis(hydroxymethyl)ethyl]propionamide},2,2′-azobis[2-methyl-N-(2-hydroxyethyl)propionamide],2,2-azobisisobutylamide dihydrate,2,2′-azobis[2-(hydroxymethyl)propionnitrile] and 2,2′-azobis(2,4,4-trimethylpentane).

The chemicals for causing the crosslinking and/or polymerizing reactionsto take place are further exemplified by tetraalkylthiuramdisulfide,morphine, disulfide compounds, alkylphenoldisulfide, salt of dithioicacid, such as Se-diethyldithiocarbamate, sulfur chloride, selenium,tellurium, zinc white, magnesium oxide, litharge, p-quinonedioxime, p,p′-dibenzoylquinoneoxime, tetrachloro-p-benzoquenone andpolo-p-dinitrosobenzene.

The quantity of the foregoing chemicals to be added is made to be 0.001mol % to 500 mol % with respect to the total quantity of all monomerunits in the polystyrene resin, preferably 0.005 mol % to 300 mol %. Thetemperature of the reaction system is made to be 0° C. to 100° C.,preferably 10° C. to 90° C. It is preferable that the concentration ofthe resin in the above-mentioned reaction system be 0.05 wt % to 39 wt%. Note that the reactions be performed in an atmosphere of inert gasof, for example, nitrogen.

As a result, the conjugate diene units in the polystyrene resin iscaused to take place the crosslinking and/or polymerizing reactions. Theforegoing reactions may be performed before the ion groups areintroduced into, the styrene or after the ion groups have beenintroduced.

Since the conjugate diene units in the polystyrene resin are crosslinkedand/or polymerized, the molecular weight Mw of the obtainedpolyelectrolyte can be made to be 600,000 or larger. The thus-obtainedelectrolyte having the large molecular weight can be used as a preferredcoagulant for disposing waste water.

In a case where the obtained polyelectrolyte is used as the coagulantfor disposing waste water, it may be used together with other additives,for example, nonionic polymeric coagulant, anionic polymer coagulant, orcationic polymer coagulant. Then, nonionic polymeric coagulant, anionicpolymer coagulant and cationic polymer coagulant which can be usedtogether with the polyelectrolyte will now be described.

<Non-Ionic Polymer Coagulant>

Polyacrylamide or polymethacrylamide, preferably polyacrylamide may beemployed.

<Anionic Polymer Coagulant>

(Metha) acrylic acid type resin may be used which is exemplified bypartial hydrolysate of polyacrylamide or polymethacrylamide; copolymerof acrylic acid or methacrylic acid and acrylamide or methacrylamide andtheir salts; ternary copolymer of acrylic acid or methacrylic acid,acrylamide or methacrylamide and 2-acrylamide-methylpropanesulfide orvinyl sulfonate or vinylmethyl sulfonic acid, preferably the partialhydrolysate of polyacrylamide, the copolymer of acrylic acid andacrylamide, its salt, and ternary copolymer of acrylic acid, acrylamideand 2-acrylamide-methylpropanesulfide.

Polystyrene sulfonate polymers may be employed which are exemplified bypolystyrene, styrene-butadiene, styrene-acrylonitrile,styrene-butadiene-acrylonitrile, styrene-(metha) acrylate,styrene-(metha) acrylate (aliphatic hydrocarbon having one to fourcarbon atoms), styrene-acrylonitrile-(metha) acrylate (aliphatichydrocarbon having one to four carbon atoms), styrene-butadiene-(metha)acrylate (aliphatic hydrocarbon having one to four carbon atoms),acrylonitrile-maleic anhydride and styrene-itaconic anhydride. Among theforegoing materials, it is preferable that any one of polystyrene,styrene-butadiene, styrene-acrylonitrile,styrene-butadiene-acrylonitrile and styrene-maleic anhydride beemployed.

The other polymers are exemplified by polyphenyleneether, polycarbonate,polyphenylenesulfide and polyethyleneterephthalate. It is preferablethat polyphenyleneether or polycarbonate be employed.

<Cationic Polymer Coagulant>

It is exemplified by a quaternized material of dialkylaminoalkyl (metha)acrylate (a quaternizing agent may be methylchloride, benzylchloride orthe like) or an acidic salt (the acidic salt may be an inorganic acidsalt, such as hydrochloride or sulphate or an organic acid salt, such asacetate) or a polymer or a copolymer of the foregoing material and(metha) acrylamide. For example, quaternized methylchloride ofdimethylaminoethylacrylate or a polymer or a copolymer of thequaternized methylchloride of dimethylaminoethylacrylate and acrylamide.

Quaternized material of dialkylaminoalkyl (metha) acrylamide or anacidic salt or a polymer or a copolymer of the foregoing material and(metha) acrylamide may be employed. For example, a copolymer ofquaternized methylchloride of dimethylaminopropylacrylamide andacrylamide may be employed.

A material obtained by denaturing polyacrylamide with cation may beemployed. For example, a material obtained by Mannich-denaturing orHofmann-decomposing polyacrylamide may be employed.

An epihalohydrin-amine condensation compound may be employed which isexemplified by a polycondensation compound of epihalohydrin andalkylenediamine having two to eight carbon atoms.

Polydimethyldiallyl ammoniumchloride may be employed.

A dicyanediamide condensation compound may be employed, which isexemplified by formalin condensation compound of dicyanediamide andammonium chloride.

Polyethyleneimine may be employed.

The polyelectrolyte according to the present invention may be mixed withthe above-mentioned polymer coagulant or the same may sequentially beadded. When the polyelectrolyte is used together with the cationicpolymer coagulant, it is preferable that the polyelectrolyte accordingto the present invention be sequentially added.

The polyelectrolyte according to the present invention may be usedtogether with a variety of inorganic agglutinant or inorganic coagulant.

Since the polyelectrolyte according to the present invention hasexcellent performance as coagulant for disposing waste water, itcontributes to preventing pollution of water and atmosphere.

The polystyrene resin for use in the present invention may be a waste aswell as a virgin material. Wastes of high-impact polystyrene(hereinafter called as “HIPS”) frequently contain a large quantity ofconjugate diene units. Therefore, the present invention is significantlyeffective as a method of recycling polystyrene resin productsmass-produced as the foregoing general-purpose resin.

A method of sulfonation by performing solid-liquid separation will nowbe described.

The foregoing method has the steps of adding and dissolving aromaticpolymers to solvents which are supplied continuously, supplyingsulfonating agent to the solution to perform sulfonating reactions,separating reactant solid materials and the solvent from each other, andreturning the separated solvent so as to be again used in thesulfonating reactions.

The aromatic polymer for use as the material to be sulfonated isexemplified by a styrene type polymer, such as polystyrene,poly-α-methylstyrene, styrene-butadiene, styrene-acrylonitrile,styrene-butadiene-acrylonitrile, styrene-(metha) acrylic acid,styrene-(metha) acrylate (aliphatic hydrocarbon having one to fourcarbons), styrene-acrylonitrile-(metha) acrylates (ariphatic hydrocarbonhaving one to four carbon atoms), styrene-butadiene-(metha) acrylates(ariphatic hydrocarbon having one to four carbon atoms), styrene-maleicanhydride, styrene-itaconic anhydride.

Among the above-mentioned materials, it is preferable that any one ofthe following material be employed: styrene-butadiene,styrene-acrylonitrile, styrene-butadiene-acrylonitrile, styrene-maleicanhydride, styrene-acrylonitrile-(metha) acrylates (ariphatichydrocarbon having one to four carbon atoms) andstyrene-butadiene-(metha) acrylates (ariphatic hydrocarbon having one tofour carbon atoms). More preferably, it is preferable thatstyrene-butadiene, styrene-acrylonitrile,styrene-butadiene-acrylonitrile or styrene-maleic anhydride beemployed,.

The foregoing copolymer may be used solely or a mixture of the foregoingcopolymers may be employed. The copolymer may be used as a mixture withpolystyrene and another polymer.

The other polymer is exemplified by polyphenyleneether, polyphenylenesulfide, polycarbonate, polyamide (a so-called Nylon),polyethyleneterephthalate and polybutylene terephthalate.

The foregoing polymer may be used solely or a mixture of the polymersmay be employed.

The aromatic polymer may be wastes or the like obtained after the use.Moreover, the aromatic polymer may contain an additive, such as apigment, a stabilizer, a flame retardant, a plasticizer, a filler oranother assistant agent.

A mixture of waste resin and a new material may be employed.

It is preferable that the molecular weight of the aromatic polymer be100 to 50,000,000, more preferably 200 to 1,000,000.

The sulfonating agent is exemplified by sulfuric anhydride, fumingsulfuric acid, chlorosulfonic acid and concentrated sulphuric acid.

The sulfonating agent may be used solely or combination of a pluralityof the sulfonating agents may be employed. It is preferable that thequantity of addition be 0.1 mol % to 300 mol % with respect to thearomatic units, more preferably 1 mol % to 200 mol %.

The sulfonating agent may be used together with a Lewis base. The Lewisbase is exemplified by alkylphosphate (triethylphosphate,trimethylphosphate or the like), dioxane, acetic anhydride, ethylacetate, ethyl palmitate, diethylether and thioxane.

It is preferable that the quantity of the Lewis base to be added be 0.01mol % to 300 mol % with respect to the aromatic units in the aromaticpolymers, more preferably 0.5 mol % to 100 mol %. If the quantity of theadded Lewis base is too small, gelled products can easily be generatedin the sulfonating reactions. If the quantity is too large, thesulfonating reaction cannot easily proceed. As a result, the yielddeteriorates.

The solvent for use in the reactions is exemplified by ariphatichalogenated hydrocarbon (preferably, 1,2-dichloroethane, chloroform,dichloromethane, 1,1-dichloroethane or the like), nitromethane,nitrobenzene, ariphatic cyclic hydrocarbon (preferably, cyclohexane,methylcyclohexane, cyclopentane or the like), preferably ariphaticcyclic hydrocarbon. The reason for this is that the ariphatic cyclichydrocarbon is able to easily dissolve unreacted aromatic polymers anddoes not dissolve aromatic polymer sulfonated materials which are thereaction products. Moreover, the solvent and the reaction solid material(aromatic polymer sulfonated material) can easily be separated from theslurry reactant solution.

The solvent may be used solely or the mixture of the foregoing solventsmay be employed. The mixture ratio of the solvent is not limitedparticularly.

The foregoing solvent may be mixed with another solvent. The solventwhich can be mixed is exemplified by paraffin hydrocarbon (having one toseven carbon atoms), acetonitrile, carbon disulfide, tetrahydrofuran,tetrahydropyran, 1,2-dimethoxyethane, acetone, methylethylketone andthiophene. Among the foregoing solvents, it is preferable that paraffinhydrocarbon (having one to seven carbon atoms), tetrahydrofuran, acetoneor acetonitrile be employed.

The mixture ratio of the above-mentioned solvent is not limitedparticularly. It is preferable that the mixture ratio be 1 volume % to100 volume %.

The above-mentioned aromatic polymer, sulfonating agent, Lewis base andthe solvent are used to perform the sulfonating reactions. In thepresent invention, the reactant solid material generated in the reactionsystem and the solvent are separated from each other prior toneutralizing the generated sulfonated material. The solvent is, as itis, recovered so as to be again used in the reactions. On the otherhand, the reactant solid material is removed by drying the residualsolvent or dissolved in water or alkaline water solution.

The alkaline material for use in the alkaline water solution, such as acompound, for example, oxide, hydride, carbonate, acetate, sulfate orphosphate of alkali metal (sodium, lithium or calcium) or an oxide ofalkaline earth metal (magnesium, calcium or the like), ammonia orprimary to tertiary alkylamine compounds, is, as it is, or in the formof water solution, gradually added so that the neutralizing Process iscompleted.

The quantity of water (the alkaline water solution) varies dependingupon the molecular weight. It is preferable that the quantity of waterbe 0.5 part by weight to 100 parts by weight with respect to one part byweight of polymer, more preferably 1 part by weight to 50 parts byweight.

If the plastics to be processed contain halogen flame retardant, halogenretardant can be separated simultaneously with introduction of the iongroups (for example, the sulfonating process).

That is, the plastic containing the-halogen retardant are processed withacid in an organic solvent, and then the ion groups are introduced intothe resin component to form a water-soluble polymer, followed byseparating the halogen retardant in the organic solvent.

In the present invention, various plastics containing the halogenretardant is processed in the present invention. The purpose and theshape of the plastics are not limited. The present invention iseffective to be used to process plastic waste which is disposed.

The halogen retardant to be contained as described above is exemplifiedby bromine retardant and chlorine retardant.

The bromine retardant is exemplified by decabromo type retardant, suchas decabromodiphenyloxide, octabromodiphenyloxide ortetrabromodiphenyloxide; and non-decabromo type retardant, such astetrabromobisphenol A (TBA), hexabroomocyclododecane,bistribromophenoxyethane, tribromophenol,ethylenebistetrabromophthalimide, TBA polycarbonate oligomer, brominatedpolystyrene, TBA epoxyoligomer or TBA epoxypolymer.

The chlorine type retardant is exemplified by chlorinated paraffin,perchlorocyclopentadecane (Dechcloran Plus) and chlorendic acid.

Among the foregoing halogen retardants, the effect of the presentinvention can be obtained as desired if the bromine retardant, inparticular, if the decabromo type retardant is employed.

The above-mentioned halogen retardant may solely be contained in theplastics or a mixture of a plurality of the above-mentioned halogenretardants may be contained. Moreover, another retardant, for example,phosphorus retardant or inorganic retardant or retardant assistant, suchas a nitrogen compound may be mixed.

The contents of the halogen retardant is not limited. The presentinvention may be applied to any content.

Although the present invention may be applied to any resin component, asignificant effect can be obtained when applied to resin having anaromatic ring.

The resin having the aromatic ring is exemplified by a styrene polymer,such as polystyrene, poly-a-methylstyrene, styrene-butadiene,styrene-acrylonitrile, styrene-butadiene-acrylonitrile, styrene-(metha)acrylic acid, styrene-acrylonitrile-(metha) acrylate (aliphatichydrocarbon having one to four carbon atoms), styrene-butadiene-(metha)acrylate (aliphatic hydrocarbon having one to four carbon atoms),styrene-maleic anhydride and styrene-itaconic anhydride.

Among the foregoing materials, it is preferable that styrene-butadiene,styrene-acrylonitrile, styrene-butadiene-acrylonitrile, styrene-maleicanhydride, styrene-acrylonitrile-(metha) ester acrylate (havingariphatic hydrocarbon having one to four carbon atoms) orstyrene-butadiene-(metha) ester acrylate (aliphatic hydrocarbon havingone to four carbon atoms) be employed, more preferablystyrene-butadiene, styrene-acrylonitrile,styrene-butadiene-acrylonitrile or styrene-maleic anhydride.

The styrene polymer may be used solely or a plurality of the styrenepolymers may be mixed. A mixture with another polymer may be employed.

The resin except for the foregoing resins is exemplified bypolyphenyleneether, polyphenylenesulfide, polycarbonate, polyamide(Nylon), polyethyleneterephthalate and polybutyleneterephthalate.

Also the foregoing resin may solely be used or a so-called alloy or alatex obtained by mixing a plurality of the resins may be employed.

The resin may contain pigment, dye, stabilizer, plasticizer, filler andanother assistant material.

Also the molecular weight of the foregoing polymer may arbitrarily bedetermined. In general, the molecular weight is about 100 to about50,000,000, preferably about 200 to about 1,000,000.

The plastic containing the halogen retardant is processed with acid inthe organic solvent, and then the ion groups are introduced. The organicsolvent for use at this time is exemplified by aliphatic halogenhydrocarbon having one carbon atom or two carbon atoms (for example,1,2-dichloroethane, chloroform, dichloromethane, 1,1-dichloroethane,tetrkchloroethane and trichloroethane), aliphatic cyclic hydrocarbon(for example, cyclohexane, methylcyclohexane and cyclopentane) andnitrated material (for example, nitromethane and nitrobenzene).

The foregoing solvent may solely be used or a plurality of the foregoingsolvents may be used. When the plurality of the solvents are used, themixture ratio is not limited particularly.

The employed solvent may be mixed with another solvent. The solventwhich can be employed in this case is exemplified by paraffinhydrocarbon (having one to seven carbon atoms), acetonitrile, carbondisulfide, tetrahydrofuran, tetrahydropyran, 1,2-dimethoxyethane,acetone, methylethylketone and thiophene. Among the foregoing solventsit is preferable that the paraffin hydrocarbon, tetrahydrofuran, acetoneor acetonitrile be employed.

The mixture ratio of the foregoing solvents is not limited particularly.

The solvent which has been used in the reactions may be recovered byextraction or distillation after the reactions have been completed so asto be again used in the reactions.

In the present invention, plastics containing the halogen retardant, forexample, waste plastics are subjected to the following reactions in theorganic solvent so that the resin components and the halogen retardantare separated from each other and recovered.

Specifically, plastic containing the halogen flame retardant is causedto react with various acids in the organic solvent to introduce the iongroups into the resin components to have water solubility so that theresin components are recovered from the aqueous layer. Moreover, thehalogen flame retardant is recovered from the organic solvent layer.

The resin component and the halogen retardant may be recycled ordisposed. Since the recovered resin component does not contain thehalogen retardant, no toxic gas is generated even if the resin componentis burnt.

The ion groups which are introduced as described above are exemplifiedby sulfonic groups, their salts, carboxylic groups, their salts, —OHgroups, their salts, —PO(OH)₂ groups or their salts.

The ion groups are introduced into the resin component by causing theresin component and the various oxidizers to react with one another.

For example, the resin component and the sulfonating agent (sulfuricanhydride, fuming sulfuric acid, chlorosulfonic acid or concentratedsulfonic acid) are allowed to react with each other so that the sulfonicgroups are introduced into the resin component. When n-butyllithium isadded and then reactions with dry ice are caused to take place,carboxylic groups can be introduced into the resin component. Whenn-butyllithium is added and reactions with water are caused to takeplace, —OH groups can be introduced. When further phosphoroustrichloride is added and then hydrolysis is performed, —PO(OH)₂. groupscan be introduced into the resin components.

When the chlorine compounds are allowed to react with the acidic groupsintroduced into the resin components as described above, neutral saltscan be introduced as ion groups.

The chlorine compounds for neutralizing the acidic groups areexemplified by oxide, hydride, carbonate, acetate, sulfate or phosphateof alkali metal (sodium, lithium or calcium) or alkaline earth metal(magnesium or calcium), ammonia and various amine compounds (primaryalkylamine, secondary alkylamine or tertiary alkylamine).

The reaction conditions under which the above-mentioned ion groups areintroduced into the resin components will now be described. It ispreferable that the reaction temperature be 0° C. to 150° C., morepreferably 10° C. to 100° C. If the temperature is lower than theabove-mentioned range, the introduction ratio of the ion groups islowered. Thus, the resin components lose the water solubility.

The reaction period of time is determined to be 20 minutes to 40 hours,preferably 30 minutes to 20 hours. If the reaction period of times isshorter than the above-mentioned length, the reactions cannotsufficiently proceed. In this case, the resin components lose the watersolubility. If the reaction period of time is longer than theabove-mentioned length, the efficiency deteriorates.

The concentration of the reaction system is made to be 0.1 wt % to 50 wt%, preferably 0.5 wt % to 30 wt %. If the concentration of the reactionsystem is lower than the above-mentioned range, the efficiencydeteriorates. What is worse, the ion groups introduction ratedeteriorates, thus resulting in that the resin components lose the watersolubility. If the concentration is too high, gelled materials andunreacted materials are generated unintentionally.

Since the ion groups are, under the above-mentioned conditions,introduced into plastics containing the halogen retardant, the resincomponents have the water solubility as the polyelectrolyte and thus theresin components exist in the aqueous layer. On the other hand, thehalogen retardant exists in a unreacted state such that the halogenretardant is dissolved in the organic solvent layer.

After the aqueous layer has been separated from the organic solventlayer and the residual solvents have been removed by distillation, itcan be used as water-soluble polyelectrolyte in a variety of purposes,such as coagulant for disposing waste water, dispersant for cement, asurface sizing agent for paper, a conductive material for paper, anantistatic agent for fiber, dispersant for coal-slurry, aqueous glue, acleaning material, a scale preventive material.

On the other hand, the halogen retardant dissolved in the organicsolvent layer is recovered as a residue after the solvent has beenremoved by distillation. Therefore, it may be used in another purpose ormay be reclaimed efficiently.

When the sulfonic acid or its salt is, as the ion group, introduced intothe polystyrene resin, that is, sulfonation is performed, sulfoncrosslinking takes place and thus, the polymers easily gel. If theconjugate diene units exist in the polystyrene resin, sulfoncrosslinking in the molecules of the polystyrene resin and betweenmolecules can be prevented. Therefore, gelling can be prevented. Sincegelling easily takes place in proportion to the molecular weight of thepolymers, the polyelectrolyte having large molecular weight cannoteasily be obtained by the conventional technique. The foregoingcontrivance enables polyelectrolyte having large molecular weight toeasily be manufactured.

The conjugate diene which is copolymerized with styrene is exemplifiedby butadiene and isoprene. The percentage content of the conjugate dienein the foregoing copolymer is made to be 0.1 mol % to 20 mol % withrespect to all monomer units, preferably 0.2 mol % to 10mol %. If thequantity of the conjugate diene units in the polystyrene resin is toosmall, side reactions in the sulfonating reactions, that is, the effectof preventing the sulfon crosslinking in the molecules and betweenmolecules cannot be obtained as desired. If the quantity of theconjugate diene units is too large, crosslinking reactions can easilytake place in the double bond portions of the conjugate diene units.Therefore, the characteristics of the sulfonated polystyrene cannot berealized. In a viewpoint of causing the original characteristic of thesulfonated polystyrene to exhibit, the quantity of the styrene units inthe polystyrene resin is made to be 80 mol % or more with respect to allof the monomer units, preferably 90 mol %.

When the conjugate diene units are allowed to exist in the polystyreneresin, the stereoscopic constraint of the rigid conjugate dienestructure prevents sulfon crosslinking in the molecules and betweenmolecules of the polystyrene resin when the sulfonating process isperformed. As a result, gelling can be prevented.

Although existence of the conjugate diene units in the polystyrene resinis able to prevent sulfon crosslinking in the molecules and betweenmolecules of the polystyrene resin, there arises a possibility that thecrosslinking reactions and polymerizing reactions take place in thedouble bond portions of the conjugate diene units. If the crosslinkingreactions or polymerizing reactions take place in the conjugate dieneunits, long-term stability of the obtained polyelectrolyte deteriorates.

Accordingly, inorganic pigment may be allowed to exist in the reactionsystem when the sulfonating process is performed. That is, theabove-mentioned polyelectrolyte may contain the inorganic pigment.

When the inorganic pigment is allowed to exist when the sulfonatingprocess is performed, the inorganic pigment traps radicals. Therefore,crosslinking reactions and polymerizing reactions in the conjugate dieneunits can be prevented. As a result, the long-term stability of thepolyelectrolyte can be improved.

Although titanium oxide may be employed as the inorganic pigment, it ispreferable that carbon black be employed.

The carbon black may be general carbon black for use in a coloringmatter for plastics, a reinforcing material or an electric conductivityagent manufactured by any one of a channel method, a furnace method or athermal method. The carbon black manufactured by any one of theforegoing method may solely be employed or a mixture of plural types ofcarbon black manufactured by different methods may be employed. It ispreferable that the average particle size of the carbon black be 5 μm to500 μm, more preferably 10 μm to 50 μm.

The contents of the carbon black in the sulfonating reaction system ismade to be 0.01 wt % to 20 wt % with respect to the polystyrene resincomponent, preferably 0.1 wt % to 10 wt %. If the content of the carbonblack is too small, the effect of preventing the crosslinking reactionsand polymerizing reactions in the conjugate diene becomes insufficient.If the content is too large, the performance as a chemical in thepolyelectrolyte deteriorates. What is worse, the cost is raised.

When the inorganic pigment is allowed to exist in the sulfonatingreaction system, the crosslinking reactions and the polymerizingreactions in the conjugate diene units can be prevented. Therefore, therange for the content of the conjugate diene units in the polystyreneresin can be widened as compared with a structure in which no inorganicpigment exists. If the inorganic pigment is allowed to exist in thesulfonating reaction system, the percentage content of the conjugatediene units with respect to all monomer units is made to be 0.05 mol %to 60 mol %, preferably 0.1 mol % to 40 mol %.

Thus, the percentage of content of the styrene units with respect to allof the monomer units is made to be 40 mol % or higher, preferably 60 mol% or higher.

If the percentage of content of the conjugate diene units is lower thanthe above-mentioned range, the effect of preventing the sulfoncrosslinking reactions becomes insufficient. In this case, thesulfonating reactions cannot stably be performed. If the percentage ofcontent of the conjugate diene is higher than the above-mentioned range,solubility into the organic solvent deteriorates when the sulfonatingreactions of the polystyrene resin are performed in the organic solvent.In this case, the reactions are performed nonuniformly. If thepercentage of content of the conjugate diene units is raisedexcessively, the percentage of content of the styrene units is lowered.Thus, also the quantity of the sulfonic acid or its salt which isintroduced is reduced. In this case, the polyelectrolyte havingsufficient water solubility cannot be obtained.

Even if the percentage of content of the styrene units is high, thepolyelectrolyte having sufficient water solubility cannot be obtained ina case where the sulfonation ratio is low. Therefore, the quantity ofthe sulfonic acid or its salt, which is introduced, is made to be 20 mol% or more, preferably 40 mol % or more.

Note that the improvement in the long-term stability attributable to theinorganic pigment is not limited to the state after the sulfonatingprocess. That is, the improvement is not limited to the introduction ofthe sulfonic acid or its salt as the ion groups. When any one of amaterial selected from a group consisting of chloromethylated aminesalt, carboxylic acid, its salt, —PO(OH)₂, its salt, —CH₂PO(OH)₂ and itssalt is introduced, existence of the inorganic pigment enables thelong-term stability of the obtained polyelectrolyte.

Although the description has been performed about the method using thesulfonic acid or the sulfonate as the ion group, a similar effect can beobtained when chloromethylated amine salt is employed as the ion group.When a chlorometylation is performed, stereroscopic constrain of therigid conjugate diene structure prevents methylene crosslinking in themolecules and between molecules of the polystyrene resin, similarly tothe sulfonating process. Therefore, gelling can be prevented. Existenceof the inorganic pigment in the reaction system when thechloromethylation is performed results in the long-term stability beingimproved.

When the polystyrene polyelectrolyte and a stabilizer are mixed,automatic oxidation of the polystyrene polyelectrolyte can be prevented.Moreover, the Long-term stability of the polystyrene polyelectrolyte canbe improved. Thus, the polystyrene polyelectrolyte having largemolecular weight can be obtained.

At this time, the stabilizer must have oxidation preventive effectand/or light stability. The stabilizer having the oxidation preventiveeffect is exemplified by the phenol type, sulfur type and phosphoroustype stabilizers exemplified as follows.

The phenol type stabilizer may be a known stabilizer which isexemplified by 2,6-di-t-butyl-P-cresol, butylated hydroxyanizole (BHA),2,6-di-t-butyl-4-methylphenol, 2,6-di-t-butyl-4-ethylphenol,3,5-diphenyl-4-methoxyphenol,stearyl-β-(3,5-di-t-butyl-4-hydroxyphenyl)propionate,tetrakis[methylene-3-(3′,5′-di-t-butyl-4′hydroxyphenyl)propionate]methane,2,2′-methylene-bis-(4-methyl-6-t-butylphenol),2,2′-methylene-bis-(4-ethyl-6-t-butylphenol),2,2′-methylene-bis(5-t-butyl-4-methylphenol),2,2′-methylene-bis-[4-methyl-6-(α-methylcyclohexyl)phenol],1,1-bis(5-t-butyl-4-hydroxy-2-methylphenyl)butane,2,2′-methylene-bis-(4-methyl-6-cyclohexylphenol),2,2′-methylene-bis-(4-methyl-6-nonylphenol),4,4′-thiobis-(3-methyl-6-t-butylphenol),4,4′-butylidene-bis-(3-methyl-6-t-butylphenol),3,9-bis[1,1-dimethyl-2-[β-(3-t-butyl-4-hydroxy-5-methylphenyl)propionyloxy]ethyl]2,4,8,10-tetraoxaspiro[5,5]undecane,1,1,3-tris-(2-methyl-4 hydroxy-5-t-butylphenyl)butane,1,1,3-tris-(6-t-butyl-4-hydroxy-2-methylphenyl)butane,2,2-bis-(5-t-butyl-4-hydroxy-2-methylphenyl)-4-n-dodecylmercaptobutane,ethyleneglycol-bis[3,3-bis(3-t-butyl-4-hydroxyphenyl)butylate],1,3,5-trimethyl-2,4,6-tris (3,5-di-t-butyl-4-hydroxybenzyl)benzene,1,1-bis (3,5-dimethyl-2-hydroxyphenyl)-3-(n-dodecylthio)-butane,4,4-thiobis(5-t-butyl-3-methylphenol),2,2-bis(3,5-di-t-butyl-4-hydroxybenzyl)maleic acid dioctadecylester,n-octadecyl-3-(4-hydroxy-3,5-di-t-butylphenyl)propionate,bis(3,3′-bis-(4-hydroxy-3′-t-butylphenyl)butylicacid]glycolester,1,3,5-tris(3′,5′-di-t-butyl-4′-hydroxybenzyl)-S-triazine-2,4,6-(1H, 3H,5H)trione,triethyleneglycol-bis[3-(3-t-butyl-4-hydroxy-5-methylphenyl)propionate],α-tricophenol (vitamin E), nordihydroguaiaretic acid,butylhydroxyanisole and gallic acid propyl.

As the sulfur type stabilizer, a known stabilizer may be employed, whichis exemplified by dilauryl-3,3′-thiodipropionate,dimyristyl-3,3′-thiodipropionate, distearyl-3,3′-thiodipropionate andpentaerythritoltetrakis (3-laurylthiopropionate).

As the phosphorus type stabilizer, a known stabilizer may be employed,which is exemplified by triphenylphsophite, diphenylisodecylhosphite,phenyldiisodecylhosphite,4,4′-butylidene-bis(3-methyl-6-t-butylphenyl-di-tridecyl) hosphite,cyclic neopentanetetrailbis (octadecylhosphite), tris(norylphenyl)hosphite, tris(mono and/or dinolylphenyl)hosphite,diisodecylpentaerythritoledihosphite,9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide,10-(3,5-di-t-butyl-4-hydroxybenzyl)-9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide,10-decyloxy-9,10-dihydro-9-oxa-10-phosphenanthrene,tris(2,4-di-t-butylphenyl)hosphite, cyclicneopentanetetrailbis(2,4-di-t-butylphenyl)hosphite, cyclicneopentanetetrailbis(2,6-di-t-butyl-4-methylphenyl)hosphite,2,2-methylenebis(4,6-di-t-butylphenyl)loctylhosphite,distearylpentaerythritoldihosphite andtetrakis(2,4-di-t-butylphenyl)-4,4′-biphenylene-di-hosphite.

As the other stabilizer, a known stabilizer may be employed, which isexemplified by erysorbic acid, sorbate soda and isopropyl citrate.

The stabilizer is not limited to the above-mentioned type having theoxidation preventive effect. A stabilizer having a light stabilizingeffect may be employed. The stabilizer having the light stabilizingeffect is exemplified by the following benzophenone type, benzotriazoletype, hindered amine type, cyanoacrylate type, salicylate type,oxalycacid anilide type stabilizers.

The benzophenone type stabilizer may be a known stabilizer which isexemplified by 2,4-hydroxybenzophenone, 2-hydroxy-4-methoxybenzophenone,2-hydroxy-4-octoxybenzophenone,2-hydroxy-4-methoxybenzophenone-5-sulfonic acid,2-hydroxy-4-dodecyloxybenzopheone, 2-hydroxy-4-octoxybenzophenone,2,2′-dihydroxy-4-methoxybenzophenone,2,2′-dihydroxy-4,4′-dimethoxybenzophenone,2-hydroxy-4-methoxy-5-sulfobenzophenone andbis(2-methoxy-4-hydroxy-5-benzoilphenyl)methane.

The benzotriazole type stabilizer may be a known stabilizer which isexemplified by 2-(2′-hydroxy-5′-methoxyphenyl)benzotriazole,2-[2′-hydroxy-3′,5′-bis(α,α-dimethylbenzyl)phenyl]-benzotriazole,2-(2′-hydroxy-3′,5′-di-t-butyl-phenyl)-benzotriazole,2-(2′-hydroxy-3′-t-butyl-5′-methylphenyl)-5-chlorobenzotriazole,2-(2′-hydroxy-3′,5′-di-t-amyl)-benzotriazole,2-(2′-hydroxy-3′,5′-di-t-butylphenyl)-5-chlorobenzotriazole,2-(2′-hydroxy-5′-t-oxtylphenyl)benzotriazole and2,2′-methylnebis[4-(1,1,3,3-tetramethylbutyl)-6-(2N-benzotriazole-2-il)phenol].

The hindered amine type stabilizer may be a known stabilizer which isexemplified by bis-[2,2,6,6-tetramethyl-4-piperidyl]sebacate,bis-[N-methyl-2,2,6,6-tetramethyl-4-piperidyl]sebacate,tetrakis(2,2,6,6-tetramethyl-4-piperidyl)-1,2,3,4-butanetetracarboxylate,bis-(1,2,2,6,6-pentamethyl-4-piperidyl)-2-(3,5-di-t-butyl-4-hydroxybenzyl)-2-n-butylmalonate,tetrakis(1,2,2,6,6-pentamethyl-4-piperidyl)-1,2,3,4-butanetetracarboxylate,a mixture of2,2,6,6-tetramethyl-4-piperydyl-1,2,3,4-butanetetracarboxylate andtridecyl-1,2,3,4-butanetetracarboxylate (hereinafter called as(2,2,6,6-tetramethyl-4-piperidyl/tridecylmixture)-1,2,3,4-butanetetracarboxylate),(1,2,2,6,6-pentamethyl-4-piperidyl/tridecylmixture)-1,2,3,4-butanetetracarboxylate,{2,2,6,6-tetramethyl-4-piperidyl/β,β,β′,β′-tetramethyl-3,9-[2,4,8,10-tetraoxaspiro(5,5)undecane]diethylmixture}1,2,3,4-butanetetracarboxylate,(1,2,2,6,6-pentamethyl-4-piperidyl/β,β,β′,β′-tetramethyl-3,9-[2,4,8,10-tetraoxaspiro(5,5)undecane]diethylmixture) 1,2,3,4-butanetetracarboxylate and poly[6-(1,1,3,3-tetrametylbutyl)imino-1,3,5-triazine-2,4-diyl][(2,2,6,6-tetramethyl-4-piperidyl)imino]hexamethylene[(2,2,6,6-tetramethyl-4-piperidyl)iminol].

The cyanoacrylate type stabilizer may be a known stabilizer which isexemplified by ethyl-2-cyano-3,3′-diphenylacrylate and2-ethylhexyl-2-cyano-3,3′-diphenylacrylate.

The salicylate type stabilizer may be a known stabilizer which isexemplified by phenylsalicylate and 4-t-butylphenylsalicylate.

The oxalyc acid anilide type stabilizer may be a known stabilizer whichis exemplified by 2-ethoxy-2′-ethyloxalycacidbisanilide.

The foregoing stabilizer may solely be employed or a mixture of two ormore types of the foregoing stabilizers may be employed. Note thatstabilizers for different systems attains a more significant effect ascompared with use of stabilizers having effects of preventing oxidationof the same systems.

The above-mentioned stabilizer is mixed with the above-mentionedpolystyrene type polyelectrolyte. At this time, the stabilizer may beadded to the water-soluble polystyrene type polyelectrolyte or the samemay be added when the ion groups are introduced into the styrene polymeror when the water-soluble styrene monomers are polymerized orcopolymerized. As an alternative to this, the stabilizer may be addedseveral times.

When the stabilizer is added to the polystyrene type polyelectrolyte,the stabilizer prevents the decomposition reactions of the polystyrenetype polyelectrolyte. Therefore, the stabilizer is able to improve thelong-term stability of the obtained polyelectrolyte composition.

If the stabilizer is added when the ion groups are introduced into thestyrene polymer or water-soluble styrene monomers are polymerized orcopolymerized, the stabilizer prevents automatic oxidation of thepolystyrene type polyelectrolyte attributable to radicals generatedduring the reactions. As a result, the stabilizer is able to preventreduction in the molecular weight of the polystyrene typepolyelectrolyte. Therefore, the stabilizer is able to prevent reductionin the molecular weight and improve the long-term stability.

It is preferable that the stabilizer be added when the ion groups areintroduced into the styrene polymers as compared with a method in whichthe same is added when the water-soluble styrene monomers arepolymerized or copolymerized. The reason for this is that the stabilizerunintentionally traps a portion of radicals generated from thepolymerization initiator and thus the effect of the polymerizationinitiator will be inhibited.

The quantity of the stabilizer to be added is made to be 0.002 parts byweight to 10 parts by weight with respect to 100 parts by weight of thepolystyrene type polyelectrolyte (the solid portion), preferably 0.01parts by weight to 2 parts by weight regardless of the timing at whichthe same is added during the manufacturing process or after thepolyelectrolyte has been manufactured. If the quantity of the stabilizeris smaller than the above-mentioned range, the effect of the stabilizerdeteriorates. If the quantity is too large, cost cannotdisadvantageously be reduced. If the quantity of the added stabilizer istoo large, the reactions for introducing the ion groups into the styrenepolymers is inhibited.

The stabilizer may previously be contained in the styrene polymers. Inthis case, the styrene polymers containing the stabilizer may be wastesdischarged from plants, retail shops or homes. If the content of thestabilizer is smaller than the above-mentioned range in a case where thewastes are used, it is preferable that the quantity smaller than theforegoing range is added. If the quantity is too large, it is preferablethat other styrene polymers which do not contain the stabilizer beadded.

If the stabilizer exists in the reaction system when the ion groups areintroduced into the styrene polymers, also the stabilizer is made to bewater soluble. Therefore, it is preferable that the stabilizer be addedduring the introduction of the ion groups in a case where non-watersoluble stabilizer is used rather than directly adding the same to thepolystyrene type polyelectrolyte.

As the stabilizer, it is most effective in terms of maintaining themolecular weight of the polystyrene type polyelectrolyte and improvingthe long-term stability to add a phenol type oxidation preventivematerial before the ion groups are introduced.

As described above, since the stabilizer is able to preventdeterioration in the polystyrene type polyelectrolyte, excellentcharacteristics can be maintained for a long time. If the stabilizer isadded when the ion groups are introduced into the styrene polymers orwhen the water-soluble styrene monomers are polymerized orcopolymerized, the stabilizer is able to prevent automatic oxidationreactions of the polystyrene type polyelectrolyte. As a result, highgrade Polystyrene type polyelectrolyte having predetermined molecularweight can be manufactured.

When the polystyrene resin is sulfonated in the solvent, the alicyclicunsaturated hydrocarbon is added to the reaction system to performsulfonation reaction with a high concentration.

The alicyclic unsaturated hydrocarbon is sulfonated when the sulfonationof the polystyrene resin is performed so as to act as a surface activeagent for the slurry which is the product. Thus, the dispersion easinessof the slurry can be improved.

Therefore, even if the reaction concentration when the sulfonation isperformed is raised, the sulfonation can stably proceed.

It is preferable that the alicyclic unsaturated hydrocarbon be in theform of a six membered ring, which is exemplified by monocyclicmonoterpene (limonene or terpinene), dicyclic monoterpene (caren,pinene, sabinene or camphene), terpinolene, cyclohexane, monoalkyl(having one to four carbon atoms), cyclohexane and terpineol.

Among the above-mentioned materials, it is preferable that any one ofthe monocyclic monoterpene (limonene, sylvestrene or terpinene),cyclohexene or methylcyclohexene be employed.

The quantity of the alicyclic unsaturated hydrocarbon to be added ismade to be 0.01 wt % to 5 wt % with respect to the styrene polymers,preferably 0.05 wt % to 1.0 wt %.

If the quantity of the alicyclic unsaturated hydrocarbon is smaller thanthe above-mentioned range, the effect of dispersion of the slurry cannotbe obtained. If the quantity is too large, the sulfonated products ofalicyclic unsaturated hydrocarbon which are by-products are generatedexcessively. Therefore, the quality (the purity is lowered) and cost areduction become unsatisfactory.

It is preferable that the alicyclic unsaturated hydrocarbon be addedbefore the sulfonation or during the sulfonation. Polystyrene resinpreviously containing the alicyclic unsaturated hydrocarbon may beemployed as the raw material to perform the sulfonation. If a recycledproduct recovered from foamed styrol contracted by limonene is used asthe raw material, the alicyclic unsaturated hydrocarbon is contained inthe raw material.

If the foamed styrol is used as the alicyclic unsaturated hydrocarbon,for example, wastes recovered by contracting by using limonene, thenecessity of adding the alicyclic unsaturated hydrocarbon when thesulfonation is performed can be removed. Thus, the process from recoveryof the foamed styrol to recycling can be realized by an integratedsystem.

The material for contracting the foamed styrol may be isoamyl acetate,benzyl propionate or ethyl acetate, as well as the limonene. If thelimonene is used, it can advantageously be used in the sulfonation as itis. The most preferable material is a liquid composition in which 1volume % to 6 volume % of ethanol is added to limonene.

As described above, the alicyclic unsaturated hydrocarbon is allowed toexist in the system during the sulfonation so that the foregoingcompound is sulfonated. The sulfonated material acts as a surface activeagent for the slurry which is the product. As a result, the dispersioneasiness of the slurry can be improved. As a result, the reactionconcentration in the sulfonation can be raised.

EXAMPLES Sulfonation Using Alicyclic Compound as Solvent

Initially, the following resins were prepared:

(a) polystyrene manufactured by Aldrich and having molecular weight Mwof 280,000;

(b) polystyrene-polydimethyldiphenyleneether alloy each having aquantity of 50 wt %;

(c) high-impact polystyrene which was a housing member for a used VHScassette tape; and

(d) foamable styrol which was a used cushioning member for a televisionset.

The foregoing resins were used such that resins (a) and (b) were in theform of pellets and (c) and (d) were obtained by crushed by a shredder.

Example 1

The temperature of solution prepared by adding 0.3 g of triethylphosphate to 70 g of cyclohexane was maintained at 50° C., and then 0.14g of sulfuric anhydride was added. Then, solution prepared by dissolving3.5 g polystyrene (a) in 66.5 g cyclohexane in a hot state of 50° C. and2.7 g of sulfuric anhydride were simultaneously dropped to theabove-mentioned solution in 60 minutes in a state where the temperaturewas maintained at 50° C. Then, the sulfonating reaction was performedfor one hour in a state where the temperature was maintained at 50±20°C.

As the reaction proceeded, slurry products were generated in thereaction solution.

Then, 15 g of water solution including 1.5 g of sodium hydroxide wasgradually added to the reaction system so that the reaction system wasneutralized. Then, the reaction system was heated so that cyclohexane inthe reaction system was removed by distillation. Finally, the pH of thewater solution of the residue was adjusted to 8 by using sodiumhydroxide. As a result, 30 wt % water solution of polyelectrolyte wasobtained which was called sample solution according to Example 1.

Although cyclohexane was allowed to remain by 40 ppm in thethus-obtained sample water solution according to Example 1, no halogencompound, as a matter of course, was detected.

Example 2

Similarly to Example 1, sulfonation reactions, a neutralizing processand removal of a solvent were performed except for apolystyrene-polydimethylphenyleneether alloy (b) being, as the polymer,used in place of polystyrene (a) and methylcyclopentane being used asthe solvent in place of cyclohexane. Thus, 30 wt % water solution of thepolyelectrolyte was obtained which was called sample water solutionaccording to Example 2.

Although methylcyclopentane was allowed to remain by 45 ppm in thethus-obtained sample water solution according to Example 2, no halogencompound, as a matter of course, was detected.

Example 3

The temperature of solution prepared by adding 0.92 g of triethylphosphate to 50 g of cyclohexane was maintained at 50° C., and then 0.17g of fuming sulfuric acid (containing SO₃ by 60 wt %) was added. Then,solution prepared by dissolving 2.4 g of high impact polystyrene (c) in120 g of cyclohexane and 3.3 g of fuming sulfuric acid weresimultaneously dropped to the above-mentioned solution in 30 minutes.Then, the temperature of the solution was maintained at 50±2° C., andthen the sulfonation was performed.

Then, 21 g of water solution including 2.1 g of sodium hydroxide wasgradually added such that the reaction system was stirred so that thereaction system was neutralized. Then, the reaction system was heated sothat cyclohexane in the reaction system was removed by distillation.Finally, the pH of the water solution of the residue was adjusted to 8by using sodium hydroxide. As a result, 20 wt % water solution ofpolyelectrolyte was obtained which was called sample solution accordingto Example 3.

Although cyclohexane was allowed to remain by 50 ppm in thethus-obtained sample water solution according to Example 3, no halogencompound, as a matter of course, was detected.

Example 4

Similarly to Example 3, sulfonation reactions, a neutralizing processand removal of a solvent were performed except for foamable styrol (d)being, as the polymer, used in place of high-impact polystyrene (c) andmethylcyclohexane being used as the solvent in place of cyclohexane.Thus, 20 wt % water solution of the polyelectrolyte was obtained whichwas called sample water solution according to Example 4.

Although methylcyclohexane was allowed to remain by 80 ppm in thethus-obtained sample water solution according to Example 4, no halogencompound, as a matter of course, was detected.

Example 5

The process to the sulfonation step was performed similarly toExample 1. After the completion of the reaction, the temperature of thesolution was lowered to the room temperature, and filtration wasperformed by using a filter.

Note that the cyclohexane in the filtrate was recovered so as to berecycled. On the other hand, the solid materials were gradually injectedinto 15 g of water solution including 1.5 g of sodium hydroxide suchthat the solution was stirred so that the solid materials were dissolvedby neutralization.

Then, the neutralized water solution was heated so that cyclohexaneallowed to remain in the neutralized water solution was removed bydistillation. Thus, 30 wt % water solution of the polyelectrolyte wasobtained which was called sample water solution according to Example 5.

Although cyclohexane was allowed to remain by 15 ppm in thethus-obtained sample water solution according to Example 5, no halogencompound, as a matter of course, was detected.

Example 6

0.3 g of triethyl phosphate was added to 70 g of cyclohexane recoveredby filtration performed in Example 5, and then the temperature wasmaintained at 50° C. Then, sulfuric anhydride was added by 0.14 g in theforegoing state. Then, a process similar to that according to Example 1was performed such that solution in which the polymers were dissolvedand sulfuric anhydride were simultaneously dropped into theabove-mentioned solution so that sulfonation was performed. Then, aneutralizing process and removal of the solvent were performed so that30 wt % water solution of polyelectrolyte was obtained which was calleda sample water solution according to Example 6.

Although cyclohexane was allowed to remain by 40 ppm in thethus-obtained sample water solution according to Example 6, no halogencompound, as a matter of course, was detected.

Example 7

The process to the sulfonation step was performed similarly to Example3. After the completion of the reaction, cyclohexane was recovered by100 g by distillation. Then, 21 g of water solution including 2.1 g ofsodium hydroxide was added to the residue solution such that the residuesolution was stirred so that the solution was neutralized.

Then, the reaction system was again heated so, that residual cyclohexanewas removed by distillation. The pH of the reaction solution wasadjusted to 8 by using sodium hydroxide so that 20 wt % water solutionof polyelectrolyte was obtained which was called sample water solutionaccording to Example 7.

Although cyclohexane was allowed to remain by 30 ppm in thethus-obtained sample water solution according to Example 7, no halogencompound, as a matter of course, was detected.

Example 8

0.92 g of triethyl phosphate was added to 50 g of cyclohexane recovereddue to the first distillation according to Example 7. In a state wherethe temperature was maintained at 50° C., 0.17 g of fuming sulfuric acidwas added. Similarly to Example 3, solution in which polymers weredissolved and fuming sulfuric acid were simultaneously dropped into thesolution so that sulfonation was performed. Then, neutralization andremoval of the solvent were performed so that 20 wt % water solution ofpolyelectrolyte was obtained which was called sample water solutionaccording to Example 8.

Although cyclohexane was allowed to remain by 45 ppm in thethus-obtained sample water solution according to Example 8, no halogencompound, as a matter of course, was detected.

Comparative Example 1

A process similar to that according to Example 1 was performed exceptfor 1,2-dichloroethane being used as the solvent in place of the solventso that water solution of a polyelectrolyte was obtained which wascalled a sample water solution according to Comparative Example 1.

Comparative Example 2

To make a comparison, partial hydrolysate of polyacrylamide (0.1 wt %)which has been employed as polymer coagulant was prepared which wascalled 2 sample water solution according to Comparative Example 2.

Evaluation of Characteristics

The thus-obtained water solution samples of the polyelectrolyte weresubjected to the following experiments to examine the effects as thecoagulants.

Initially, solution in which aluminum sulfate in a quantity of 500 ppmwas added to waste water (pH of which was 3.4, which contained suspendedmaterials in a quantity of 0.4 wt % and the chemical oxygen demand ofwhich was 60 ppm) obtained from an electronic parts manufacturing plantwas prepared as suspended solution for evaluating the coagulationcharacteristic. The solution for evaluating the coagulationcharacteristic in a quantity of 100 ml was injected into a 200 mlmeasuring cylinder. Then, sample water solutions according to Examples 1to 8 and Comparative Examples 1 and 2 were injected into the suspendedsolution for evaluating the coagulation characteristic such that thequantity of the polymer was 10 ppm. Immediately after the injection, themeasuring cylinder was vertically rotated ten times to stir thesolution, and then the measuring cylinder was allowed to stand. Then,the sedimentation rate of suspended particles, turbidity of thecoagulated filtrate and the content of dicloroethane (DCE) weremeasured. Results were shown in

TABLE 1 Sedimentation Turbidity Content of DCE in Rate (m/hour) (ppm)Filtrate (ppm) Example 1 25 48 not higher than allowable limit Example 220 51 not higher than allowable limit Example 3 23 35 not higher thanallowable limit Example 4 24 50 not higher than allowable limit Example5 23 48 not higher than allowable limit Example 6 24 50 not higher thanallowable limit Example 7 22 40 not higher than allowable limit Example8 23 43 not higher than allowable limit Comparative 24 52 0.3 Example 1Comparative 24 73 not higher than Example 2 allowable limit

Note that Article 9 and so forth of Japanese Sewage Water Law (effluentstandard with respect to sewage) regulates that the content of1,2-dichloroethane in effluent must. be 0.04 ppm or lower.

As can be understood from Table 1, all of the sample water solutionsaccording to Examples 1 to 8 had basic characteristics as the polymercoagulant and effects of lowering the turbidity of the filtrate afterthe coagulation was superior to that of the sample water solutionaccording to Comparative Example 2 which was the conventional polymercoagulant. Although sample water solution according to ComparativeExample 1 had the coagulating effect, the content of dichloroethane inthe filtrate was larger than the allowable limit. Therefore, the samplewater solution according to Comparative Example 1 was not used as thecoagulant.

Crosslinking by Means of Conjugate Diene Units

Initially, the following resins were prepared:

(e) polystyrene containing no conjugate diene unit, having molecularweight Mw of 280,000 and manufactured by Aldrich;

(f) styrene-butadiene copolymer having a composition such thatstyrene:butadiene=40:60 (mol %) and molecular weight Mw of 200,000 andmanufactured by Scientic Polymer;

(g) high-impact polystyrene which was a compound product, whichcontained butadiene by 2 mol % and which had molecular weight Mw of220,000;

(h) high-impact polystyrene which was a waste of cassette case of VHStape, which contained butadiene by 1 mol % and which had molecularweight Mw of 180,000; and

(i) high-impact polystyrene which was a waste of housing for atelevision set, which contained butadiene by 4 mol % and which hasmolecular weight Mw of 230,000.

Note that the resins (h) and (i) were obtained by crushing the rawmaterial by a shredder.

Example 9

The temperature of solution prepared by adding 0.6 coagulant triethylphosphate to 70 coagulant of 1,2-dichloroethane was maintained at 20° C.to 25° C., and then 0.27 coagulant of sulfuric anhydride was added tothe above-mentioned solution. Then, the temperatures of solution inwhich 7 g of high-impact polystyrene (g) was dissolved in 63 g of1,2-dichloroethane and 4.3 g of sulfuric anhydride were maintained atthe above-mentioned level and dropped in 60 minutes. After the addition,water was added, and then the solvent was removed by distillation sothat 20 wt % water solution of polystyrene sulfonate was obtained.

Then, the residual solution was heated to 50° C., and then 0.15 g ofammonium persulfate was added in nitrogen atmosphere, and then thesolution was matured for one hour.

Then, water solution including sodium hydroxide was gradually added tothe above-mentioned reaction system such that the water solution wasstirred so that the reaction system was neutralized.

As a result of the above-mentioned process, polystyrene sulfonate sodahaving molecular weight Mw of 1,400,000 was obtained. The obtained watersolution of the polyelectrolyte was called as sample water solutionaccording to Example 9.

Example 10

A process similar to that according to Example 1 was performed exceptfor high-impact polystyrene (h) being employed in place of high-impactpolystyrene (g) so that polystyrene sulfonate soda having molecularweight Mw of 900,000 was obtained. The obtained water solution of thepolyelectrolyte was called as sample water solution according to Example10.

Example 11

The temperature of solution in which 0.02 g of AlBn was added to 50 g ofcyclohexane was maintained at 70° C. in a nitrogen atmosphere. Then,solution in which 2.4 g of high-impact polystyrene (g) and 0.92 g oftriethyl phosphate were dissolved in cyclohexane and 3.5 g of fumingsulfuric acid were, in a state where their temperatures were made to bethe same, simultaneously dropped in 30 minutes. Then, the temperature ofthe solution was maintained at 70±2° C. and reactions were performed forone hour.

Then, water solution including sodium hydroxide was, while beingstirred, gradually added to the reaction system so that the solution wasneutralized. Then, the solution was heated so that cyclohexane in thereaction system was removed by distillation.

As a result of the above-mentioned process, polystyrene sulfonate sodahaving molecular weight Mw of 1,800,000 was obtained. The obtained watersolution of the polyelectrolyte was called as sample water solutionaccording to Example 11.

Example 12

The temperature of solution in which 2.44 g of triethyl phosphate wasadded to 70 g of 1,2-dichloroethane was maintained at 55° C. to 60° C.Then, solution in which 6.93 g of high-impact polystyrene (i) wasdissolved in 63 g of 1,2-dichloroethane and 8.4 g of 60% fuming sulfuricacid were simultaneously dropped to the above-mentioned solution in 60minutes, followed by maturing the solution for 30 minutes.

Then, water solution including sodium hydroxide was, while beingstirred, gradually added to the reaction system so that the solution wasneutralized. Then, the neutralized mixture was heated at the roomtemperature so that 1,2-dichloroethane was removed from theabove-mentioned reaction system by distillation.

Then, the above-mentioned residual solution was heated to 60° C., andthen 30 wt % peroxide solution was added under a nitrogen atmosphere,and then the solution was matured for two hours.

As a result of the above-mentioned process, polystyrene sulfonate sodahaving molecular weight Mw of 2,500,000 was obtained. The obtained watersolution of the polyelectrolyte was called as sample water solutionaccording to Example 12.

Example 13

0.3 g of 2,2-azobis (4-methoxy-2,4-dimethylvaleronitrile) was added tosolution in which 5 g of high-impact polystyrene (h) was added to 20 gtetrachloroethane. Then, the solution was stirred for one hour in astate where the solution was heated to 60° C. in a nitrogen air flow.

Then, the above-mentioned solution was added to 45 g ofchloromethylether, and then 15 g of aluminum chloride was graduallyadded. In a state where the above-mentioned temperature was maintained,the solution was stirred for three hours. After the reaction, unreactedchloromethylether was distillated under reduced pressure, and thenammonia water having the same mol as that of the chloromethyl groupsintroduced into the polystyrene resin was added.

As a result of the above-mentioned process, polychloromethylstyreneammonium salt having molecular weight Mw of 2,100,000 was obtained. The.obtained water solution of the polyelectrolyte was called as samplewater solution according to Example 13.

Comparative Example 3

A process similar to that according to Example 9 was performed exceptfor polystyrene (e) being employed in place of high-impact polystyrene(g) so that polystyrene sulfonate soda having molecular weight Mw of450,000 was obtained. The obtained water solution of the polyelectrolytewas called as sample water solution according to Comparative Example 3.

Comparative Example 4

A process similar to that according to Example 9 was performed exceptfor styrene-butadiene copolymer (f) being used in place of high-impactpolystyrene (g) so that sulfonation was performed. Then, ammoniumpersulfulate was added.

However, gelled substances were generated in the reaction System whenthe ammonium persulfulate was added. Thus, the water solutionpolyelectrolyte was not obtained.

Comparative Example 5

In a state where the temperature of solution in which 0.92 g of triethylphosphate was added to 50 g of cyclohexane was maintained at 70° C.,0.17 g of 60% fuming sulfuric acid was added. Then, solution in which2.4 g of high-impact polystyrene (9) was dissolved in 120 g ofcyclohexane and 3.3 g fuming sulfuric acid were simultaneously droppedinto the above-mentioned solution in 30 minutes in a state where theirtemperatures were made to be the same. Then, reactions were performedfor one hour in a state where the temperature of the solution wasmaintained at 70±2° C.

Then, water solution including sodium hydroxide was, while beingstirred, gradually added to the above-mentioned reaction system so thatthe reaction system was neutralized. Then, the solution was heated sothat cyclohexane in the reaction system was removed by distillation.

As a result of the above-mentioned process, polystyrene sulfonate sodahaving molecular weight Mw of 420,000 was obtained. The obtained watersolution of the polyelectrolyte was called as sample water solutionaccording to Comparative Example 5.

Comparative Example 6

In a state where the temperature of solution in which 2.44 g of triethylphosphate was added to 70 g of 1,2-dichloroethane was maintained at 55°C. to 60° C., solution in which 6.93 g of high-impact polystyrene (i)was dissolved in 63 g of 1,2-dichloroethane and 9.33 g of 60% fumingsulfuric acid were simultaneously dropped in 60 minutes. Then, thesolution was matured for 30 minutes.

Then, water solution including sodium hydroxide was, while beingstirred, gradually added to the above-mentioned reaction system so thatthe reaction system was neutralized. Then, the solution was heated sothat 1,2-dichloroethane in the reaction system was removed bydistillation.

As a result of the above-mentioned process, polystyrene sulfonate sodahaving molecular weight Mw of 440,000 was obtained. The obtained watersolution of the polyelectrolyte was called as sample water solutionaccording to Comparative Example 6.

Comparative Example 7

A similar process to that according to Example 13 was performed exceptfor polystyrene (e) being used in place of high-impact polystylene (h)so that polychloromethylstyrene ammonium salt having molecular weight Mwof 390,000 was obtained. The obtained water solution of thepolyelectrolyte was called as sample water solution according toComparative Example 7.

Evaluation of Characteristic

The polystyrene resins were refined variously, thus resulting in thatpolyelectrolytes according to Comparative Examples 3 to 7 had molecularweight Mw of 500,000 or smaller. On the other hand, the polyelectrolytesaccording to Examples 9 to 13 had molecular weight Mw of 900,000 orlarger s.

The results will individually be evaluated. Comparative Examples 3 and 7using polystyrene (c) having no conjugate diene unit resulted in thatthe polyelectrolyte having large molecular weight was not obtained evenif the polymerization initiator was added. Comparative Examples 5 and 6using high-impact polystyrene (g) and (i) containing conjugate dieneunits resulted in that the polyelectrolyte having large molecular weightcould not be obtained because crosslinking and/or polymerizing was notperformed. Comparative Example 4 using copolymer (f) containingconjugate diene units in an excessively large quantity resulted in thatgellation occurred when the crosslinking was performed. Thus, thewater-soluble polyelectrolyte could not be obtained.

On the other hand, Examples 9 to 13 respectively using high-impactpolystyrene (g) to (i) containing the conjugate diene units in anappropriate quantity and. subjected to crosslinking and/or. polymerizingreactions resulted in that the polyelectrolyte having large molecularweight was obtained. As can be understood from results of comparisonsamong Examples 9, 10 and 12, use of conjugate diene units in theemployed polystyrene resin in a proper quantity permits wastes to beused as the polystyrene resin. Moreover, a fact can be understood fromresults of comparisons between Examples 9, 11 and 12 that thecrosslinking agent may be added after the ion groups have beenintroduced, the crosslinking agent and the sulfonating agent maysimultaneously be added and the crosslinking agent may be added afterthe ion groups have been neutralized. As a result of a comparisonbetween Examples 10 and 13, the ion groups to be introduced into thepolystyrene resin may be either sulfonic acid soda or chloromethylatedammonium salt.

As a result, a fact was detected that the method having the step ofintroducing ion groups into polystyrene resin containing the conjugatediene units in an adequate quantity and the step of crosslinking and/orpolymerizing the conjugate diene units in the resin enableswater-soluble polyelectrolyte having large molecular weight to beobtained.

Moreover, the characteristics of the obtained sample water solutions toserve as the coagulant for disposing waste water were evaluated.

Initially, the sample water solution of a type composed of thepolyelectrolyte into which the sulfonic acid soda had been introduced asthe ion groups was evaluated.

Specifically, solution in which 50 ppm of aluminum sulfate was added towaste water from an electronic part plant (pH=6.0 and concentration ofsuspended materials (ss)=500 ppm) was prepared as the suspended solutionfor-evaluating the coagulation. Then, 100 ml of suspended solution wasinjected into 200 ml measuring cylinder having a stopper, followed byinjecting the sample water solutions according to Examples 9 to 12 andComparative Examples 3, 5 and 6 in a quantity with which theconcentration of the resin component in the suspended solution forevaluating coagulation was made to be 2.0 ppm. Immediately after this,the measuring cylinder was vertically rotated ten times, and then thesame was allowed to stand. Then, the sedimentation rate of the suspendedparticles and the turbidity of the filtrate after the coagulation weremeasured. Moreover, similar measurements were performed about a processin which 1 ppm of the sample water solution according to Example 10 and1 ppm of commercial coagulant A (partial hydrolysate of polyacrylamide)were mixed and a process in which 2 ppm of the commercial coagulant Awas solely used. Results were shown in Table 2.

TABLE 2 Sedimentation Rate Turbidity (m/hour) (ppm) Example 9 25 8Example 10 20 10  Example 11 28 5 Example 12 32 5 Example 10 + A 22 7 A20 17  Comparative 15 14  Example 3 Comparative 17 16  Example 5Comparative 17 13  Example 6

As can be understood from Table 2, the sample water solutions accordingto the examples had basic characteristics as the polymer coagulantsuperior to those of the sample water solution according to ComparativeExample 6 and those of the commercial coagulant. Moreover, another factwas detected that a satisfactory effect could be obtained if the samplewater solution according to the example and the commercial coagulant areused together.

Then, the sample water solution composed of the polyelectrolyte intowhich chloromethylated ammonia salt had been introduced as the ion groupwas evaluated.

Specifically, mixed sludge (pH=6.8 and concentration of suspendedmaterials (ss)=1.1 wt %) disposed from a sewerage disposal plant wasprepared as suspended solution for evaluating coagulation. In a statewhere the suspended solution was stirred in a jar tester, the samplewater solutions according to Example 13 and Comparative Example 7 wereinjected in a quantity with which the resin component is made to be 0.5wt % per the suspended materials (ss). Then, the solution was allowed tostand, and then the sedimentation rate of the suspended particles andthe turbidity of the filtrate after the coagulation were measured.Moreover, a process in which a mixture of the sample water solutionaccording to Example 13 and commercial coagulant B (quaternizedN,N-dimethylaminomethylacrylatemethylchloride) and a process in whichthe above-mentioned commercial coagulant B was solely used weresimilarly evaluated. Results were shown in Table 3.

TABLE 3 Sedimentation Rate Turbidity (m/hour) (ppm) Example 13 35 20Example 13 + B 38 25 B 34 40 Comparative  5 82 Example 7

As can be understood from Table 3, the sample water solution accordingto Example 13 had basic characteristic as the polymer coagulant superiorto those of Comparative Example 7 and the commercial coagulant. Anotherfact was detected that use of both of the sample water solutionaccording to Example 13 and the commercial coagulant attains asatisfactory effect.

As a result, a fact was detected that the polyelectrolyte in which theion groups were introduced into the polystyrene having the conjugatediene units in an adequate quantity and in which the conjugate dieneunits in the resin are crosslinked and/or polymerized had significantlyexcellent characteristics as the coagulant for disposing waste water.

Sulfonation by Means of Solid-Liquid Separation Method

A sequential process for sulfonating aromatic polymers by a solid-liquidseparation method will now be described with reference to FIG. 1.

Aromatic polymers are sulfonated by continuously supplying solvent froma solvent tank 1 by a pump 2, and then the aromatic polymers are addedand dissolved in the solvent (see FIG. portion (a) of FIG. 1). As analternative to this, aromatic polymers dissolved in solvent are added.

At this time, the solution may be heated or heating may be omitted. Toimprove the processing performance, it is preferable that heat beperformed.

The period of time required for the aromatic polymer to be dissolved inthe aromatic polymers is somewhat affected by the temperature and theconcentration of the solution, the molecular weight and the type of thearomatic polymers. However, the period of time is generally 10 minutesto two hours.

The concentration of the aromatic polymer solution is made to be 1 wt %to 30 wt % when chlorine type solvent is used, preferably 5 wt % to 20wt %. When non-chlorine type solvent is used, the concentration is madeto be 0.5 wt % to 20 wt %, preferably 1 wt % to 15 wt %.

Then, Lewis base is injected if necessary (see portion (b) of FIG. 1).

It is preferable that Lewis base be added to prevent crosslinkingreactions when sulfonation is performed. The Lewis base may be dissolvedin the solvent simultaneously with the above-mentioned aromatic polymer.The working efficiency can be improved when the Lewis base is addedsimultaneously.

Then, the sulfonating agent is injected into the aromatic polymers torealize a required sulfonation ratio (see portion (c) of FIG. 1).

The temperature of the solution is made to be 0° C. to 100° C. though itvaries depending upon the type of the solvent. It is preferable that thetemperature be 20° C. to 80° C.

It is preferable that the sulfonating agent be injected by dropping tocontrol the reactions.

After the sulfonating agent has been injected, reactants are depositedin the form of slurry as the reactions proceed. The period of time forwhich the reactions proceed is 10 minutes to 2 hours although it variesdepending upon the temperature. The deposited slurry (reactant solidmaterials) are separated from the solvent by a solid-liquid separator 3.

After reactions have been completed, it is preferable that the reactionsolution be cooled to enhance deposition of the slurry.

The above-mentioned reactions may be performed in the atmosphere or ininert gas, such as nitrogen. It is preferable that the reactions beperformed in the inert gas to prevent oxidation of the aromaticpolymers.

The operation for mixing the raw materials may be performed in either areaction tank or a line mixer.

The separated solvent is returned to the solvent tank 1 by a pump 4 andso forth so as to be returned to the original line.

The amount of loss of the returned solvent is replenished by a solventreplenishing tank 5 if necessary.

Although portions of unreacted Lewis base and sulfonating agent aremixed with the returned solvent, the quantities of addition of theforegoing raw materials are made to be constant because a stationarystate is realized owning to a continuous operation.

The separated slurry is processed as follows:

(1) The slurry dried with heat and/or in vacuum in a drier 6 so as to beformed into solid aromatic sulfonated materials.

(2) The slurry is dissolved in water in a dissolving tank 7 so as to beformed into water solution of aromatic polymers into which sulfonic acidhas been introduced.

(3) The slurry is neutralized with alkaline water solution in adissolving tank 8 so as to be formed into aromatic polymer solution intowhich sulfonate has been introduced.

The solid-liquid separator 3 for separating the solvent and the slurryfrom each other may be a sedimentation separator, a filter apparatus (inthe form of a plate, cylinder, disc or a belt shape), a compressor (of afilter press type, tube press type, screw press type belt press type,tower press type or a disc press type), a centrifugal separator (adecanter type, screw discharge type or an extrusion plate type), floattype separator or a cyclone.

FIGS. 2 and 3 show specific structures of the solid-liquid separators.

The apparatus shown in FIG. 2 has two dissolving tanks 11 and 12 to eachof which a mesh M for filtering the slurry is attached. The dissolvingtanks 11 and 12 are respectively provided with stirrers 13 and 14, areactant supply lines for supplying reaction solution into the tanks,water supply lines for supplying water solution, such as water andalkali solution, return lines for recovering the solvent in the tanksand solution recovering lines.

The reaction solution supply lines are opened/closed by valves 15 and16, the water supplying lines are opened/closed by valve 17 and 18, thereturn lines are opened/closed by valves 19 and 20 and the solutionrecovery lines are opened/closed by valves 21 and 22.

One of the tanks of the apparatus, for example, the dissolving tank 12is provided with a valve 16 for supplying reaction solution so that thereaction solution is supplied into the tank. Moreover, reactant solidmaterials are trapped by the mesh M. In addition, the solvent isreturned to the return line when the valve 20 is opened.

In the other dissolving tank 11, the line for supplying the reactionsolution and the line for returning the solvent, that is, the valves 15and 19 are closed and the valve 17 is opened so that water or alkalinesolution for dissolving the reactant solid materials trapped by the meshM is introduced. Thus, water solution of aromatic sulfonic acid andaromatic sulfonate is manufactured. The water solution is recovered fromthe solution recovery line when the valve 21 is opened.

The above-mentioned operation is alternately repeated in the dissolvingtanks 11 and 12.

On the other hand, the apparatus shown in FIG. 3 is provided with atriangular pyramid mesh S and having a reaction solution supply pipe 32is disposed in the upper portion of a dissolving tank 31. Moreover, asolvent recovery pipe 33 is provided to slightly project over the bottomof the dissolving tank 31. The triangular pyramid mesh S is set to coverthe solvent recovery pipe 33.

In the above-mentioned apparatus, reaction solution is supplied from thereaction solution supply pipe 32 disposed in the upper portion asdescribed above. At this time, reactant solid materials are trapped bythe mesh S, and then gradually dropped to the lower portion of the tankowning to the gravity. The dropped reactant solid materials aredissolved in water and alkali solution so that water solution ofaromatic polymers into which sulfonic acid or sulfonate has beenintroduced is manufactured.

The solvent is allowed to pass through the triangular pyramid mesh S,and then returned to the reaction line from the solvent recovery pipe 33disposed in the lower portion of the tank.

As a result of the above-mentioned method and apparatus, the solvent usein the sulfonation reactions can be recovered in a state where it doesnot contain water because it is not brought into contact with water, thealkaline compound and its water solution. Thus, the recovered solventcan be again used in the sulfonation reactions as it is. As a result,the working efficiency can be improved, resources can effectively beused and the cost can be reduced.

Separation of Halogen type Flame Retardant

In this case, high-impact polystylene (containing decabromodiphenyloxideDBDPO by 10 wt %) used as a back cover for a television set and crushedby a shredder was employed as the plastic material containing halogentype frame retardant.

Solution, in which 6.93 g of the crushed waste was dissolved in 63 g of1,2-dichloroethane, and 9.33 g of 60% fuming sulfuric acid were, in 60minutes, simultaneously dropped into solution in which 2.44 g oftriethyl phosphate was added to 70 g of 1,2-dichloroethane. During thedropping process, the temperature of the reaction system was controlledto be 20° C. to 25° C.

As the sulfonating reactions proceeded, slurry reactants were generated.After the dropping process had been completed, maturing was performedfor 30 minutes. Then, 5 wt % sodium hydroxide solution was added so thatthe reaction system was neutralized. At this time, the slurry reactionreactants were dissolved in the sodium hydroxide solution.

After the neutralization had been completed, the solution was separatedinto an organic layer (the lower layer) and water layer (the upperlayer). Then, the organic solvent layer, which was the lower layer, wasremoved through the bottom portion of the reactor.

The water layer left in the reactor was heated so that the residualsolvent was removed. As a result, water-soluble polyelectrolyte wasobtained which was permitted to be used variously.

Note that the water layer did not contain decabromodipheyloxide, whichwas the flame retardant (confirmed by gas chromatography of the waterlayer portion after the solvent had been extracted).

The organic solvent layer removed from the reactor was distillated sothat the organic solvent was recovered. As the residue,decabromodipheyloxide, which was the flame retardant was recovered.

Introduction of Conjugate Diene Units

Initially, the following resins were prepared:

(j) polystyrene containing no conjugate diene unit, having molecularweight MW of 280,000 and manufactured by Aldrich;

(k) styrene-butadiene copolymer having composition asstyrene:butadiene=85:15 (mol %) and manufactured by Polyscience;

(1) high-impact polystylene which was a waste of VHS cassette case andcontained butadiene by 1 mol %;

(m) high-impact polystylene which was a waste of housing of a televisionset and which contained butadiene by 5 mol %; and

(n) styrene-butadiene copolymer having composition asstyrene:butadiene=40:60 (mol %) and manufactured by Scientificpolymer.

As the resins (1) and (m) were obtained by crushing by using a shredder.

Example 14

6 g of styrene-butadiene copolymer (g) was dissolved in 54 g of1,2-dichloroethane, and then the temperature of the solution wasmaintained at 50° C. Then, 7.7 g of 60% fuming sulfuric acid was droppedin 30 minutes, and then the temperature was maintained at theabove-mentioned level so that sulfonation was completed.

Although slurry reactants were generated in the reaction solution as thereactions proceeded, gelled substances were not allowed to adhere to thewall surface of the reaction container.

Then, sodium hydroxide solution was gradually added into the reactionsystem so that the solution was neutralized. Then, the solution washeated so that 1,2-dichloroethane in the reaction system was removed bydistillation. Then, pH of water solution of the residue was finallyadjusted to 8 by using sodium hydroxide. The thus-obtainedpolyelectrolyte solution was adjusted in such a manner that theconcentration of the resin was 0.1 wt %. The prepared solution wascalled as sample water solution according to Example 14.

Example 15

The temperature of solution in which 0.1 g triethyl phosphate was addedto 70 g of cyclohexane was maintained at 50° C., and then 0.14 g ofsulfuric anhydride was added. Then, solution, in which 6 g ofstyrene-butadiene copolymer (k) was dissolved in 66.5 g cyclohexane, and2.7 g of sulfuric anhydride were simultaneously dropped into theabove-mentioned solution in 60 minutes in a state where theirtemperature of the solution was maintained at 50° C. Then, thetemperature of the solution was maintained at 50±2° C., and thensulfonation was performed for one hour.

Also slurry products were generated in the reaction solution as thereactions proceeded, gelled substances were not allowed to adhere to thewall surface of the reaction container until reactions were completed.

Then, neutralization was performed similarly to Example 14, and then thesolution was heated so that cyclohexane in the reaction system wasremoved by distillation. The pH of the water solution of the residue wasfinally adjusted to 8 by using sodium hydroxide.

The thus-obtained polyelectrolyte solution was adjusted in such a mannerthat the concentration of the resin was 0.1 wt %. The prepared solutionwas called as sample water solution according to Example 15.

Example 16

The temperature of solution in which 1.2 g of triethyl phosphate wasadded to 70 g of cyclohexane was maintained at 20° C. to 25° C. Then,solution, in which 6.93 g of high-impact polystylene (1) was dissolvedin 1,2-dichloroethane, and 9.33 g of 60% fuming sulfuric acid weresimultaneously dropped to the above-mentioned solution in 60 minutes ina state where their temperature was maintained at 20° C. to 25° C. As aresult, sulfonation was performed.

Also slurry products were generated in the reaction solution as thereactions proceeded, gelled substances were not allowed to adhere to thewall surface of the reaction container until reactions were completed.

Then, neutralization was performed similarly to Example 14, and then thesolution was heated so that 1,2-dichloroethane in the reaction systemwas removed by distillation. The pH of the water solution of the residuewas finally adjusted to 8 by using sodium hydroxide.

The thus-obtained polyelectrolyte solution was adjusted in such a mannerthat the concentration of the resin was 0.1 wt %. The prepared solutionwas called as sample water solution according to Example 16.

Example 17

A process similar to that according to Example 15 was performed exceptfor high-impact polystylene (m) being used so that sulfonation wasperformed.

Also slurry products were generated in the reaction solution as thereactions proceeded, gelled substances were not allowed to adhere to thewall surface of the reaction container until reactions were completed.

Then, neutralization was performed similarly to Example 14, and then thesolution was heated so that cyclohexane in the reaction system wasremoved by distillation. The pH of the water solution of the residue wasfinally adjusted to 8 by using sodium hydroxide.

The thus-obtained polyelectrolyte solution was adjusted in such a mannerthat the concentration of the resin was 0.1 wt %. The prepared solutionwas called as sample water solution according to Example 16.

Comparative Example 8

A process similar to that according to Example 14 was performed exceptfor polystyrene (j) being used as the resin so that sulfonation wasperformed.

In this case, bulk shape gelled substances were generated in thereaction solution 10 minutes after start of the dropping process. Whenthe dropping operation was completed, the gelled substances wereunintentionally allowed to adhere to the wall surface of the reactioncontainer. Even after alkaline solution was added similarly to Example14, the gelled substance could not be dissolved.

Comparative Example 9

A process similar to that according to Example 15 was performed exceptfor polystyrene (j) being used as the resin so that sulfonation wasperformed.

Also slurry products were generated in the reaction solution as thereactions proceeded, gelled substances were not allowed to adhere to thewall surface of the reaction container until reactions were completed.

Then, neutralization was performed similarly to Example 14, and then thesolution was heated so that cyclohexane in the reaction system wasremoved by distillation.

However, white insoluble substances (polystyrene insufficientlysulfonated) was generated in the water solution of the residue. Theinsoluble substances were removed by using a filter, and then the finalpH of the filtrate was adjusted to 8 by using sodium hydroxide.

The thus-obtained polyelectrolyte solution was adjusted in such a mannerthat the concentration-of the resin was 0.1 wt %. The prepared solutionwas called as sample water solution according to Comparative Example 9.

Comparative Example 10

A process similar to that according to Example 16 was performed exceptfor polystyrene (n) being used as the resin so that sulfonation wasperformed.

In this case, bulk shape gelled substances were generated in thereaction solution as the sulfonation proceeded. When the droppingoperation was completed, the gelled substances were unintentionallyallowed to adhere to the wall surface of the reaction container. Evenafter alkaline solution was added similarly to Example 14, the gelledsubstance could not substantially be dissolved.

Evaluation of Characteristics

As described above, various resins were sulfonated. As a result, thecases according to Examples 14 to 17 where polystyrene resin (k), (l)and (m) each containing the conjugate diene units in a proper quantitywere free from generation gelled substances and thus the sulfonation wasstably performed. In Comparative Examples 8 and 9 in which polystyreneresin (j) which did not contain the conjugate diene was used and inComparative Example 10 in which polystyrene resin (n) containing theconjugate diene units at an excessively high ratio, gelled substanceswere generated during the sulfonation process or insoluble resinunintentionally left in water.

As a result, when polystyrene resin containing the conjugate diene unitsby 0.1 mol % to 20 mol % with respect to all of monomer units issulfonated, a polyelectrolyte having sufficient water solubility andfree from gellation can be obtained.

The effects as the coagulant of the sample water solutions according toExamples 14 to 16 including resins which were sufficiently refined intowater-soluble polyelectrolyte and the sample water solution according toComparative Example 9 including resins a poor portion of which wasrefined into water-soluble polyelectrolyte were examined.

Specifically, solution in which aluminum sulfate was added to 5.0 wt %kaoline solution in such a manner that the aluminum sulfate was 0.1 wt %with respect to pure water was prepared as suspended solution forevaluating coagulation. Then, 100 ml of the suspended solution wasinjected into a 200 ml measuring cylinder having a stopper, and then thesample water solutions according to Example 14 to 17 and ComparativeExample 9 were injected into the measuring cylinder in a quantity withwhich the resin component was made to be 20 ppm. Immediately after this,the measuring cylinder was vertically rotated ten times, and thenallowed to stand. Then, the sedimentation rate of the suspendedparticles and the turbidity of the filtrate after the coagulation weremeasured. Results were shown in Table 4.

TABLE 4 Sedimentation Rate Turbidity (cm/minute) (ppm) Example 14 17 22Example 15 15 21 Example 16 15 24 Example 17 18 23 Comparative 12 30Example 9

As can be understood from Table 4, the sample water solutions accordingto Examples 14 to 17 had basic characteristics as the polymer coagulant.On the other hand, the sample water solution according to ComparativeExample 9 resulted in slow sedimentation rate and an insufficient effectof preventing lowering in the turbidity of the filtrate. The reason whythe coagulating effect of the sample water solution according toComparative Example 9 was unsatisfactory was that non-uniformintroduction of sulfonation into the sample water solution according toComparative Example 9 (resins sulfonated at high ratio and thosesulfonated insufficiently coexisted) caused the portion having thecomposition which is effective to serve as the coagulant was too smallwith respect to the overall quantity of the addition.

Addition of Inorganic Pigment

In this experiment, an effect obtainable from causing carbon black asinorganic pigment to exist when the ion groups are introduced will beconfirmed.

Initially, the following resins were prepared:

(o) high-impact polystylene containing butadiene by 2 mol %, containingno carbon black and having molecular weight Mw of 220,000;

(p) high-impact polystylene which was a waste of VHS cassette case,which contained butadiene by 1 mol % and carbon black by 1 wt % and themolecular weight Mw of which was 180,000;

(q) an alloy of high-impact polystylene-polyphenylneeether, which was awaste of housing for a CD-ROM driver, which contained butadiene inhigh-impact polystylene by 2 mol % and carbon black by 2 wt % withrespect to overall quantity of the alloy and in which the molecularweight Mw of the high-impact polystylene was 200,000; and

(r) high-impact polystylene which was a waste of a housing of atelevision set, contained butadiene by 4 mol % and carbon black by 1 wt% and the molecular weight of which was 230,000.

The resins (p) to (r) were obtained by crushing the materials by ashredder.

As the carbon black, a standard material (HCC type having an averageparticle size of 9 μm to 14 μm) for a color product was prepared.

Example 18

The temperature of solution in which 0.6 g of triethyl phosphate and 0.5g of carbon black were added to 70 g of 1,2-dichloroethane wasmaintained at 20° C. to 25° C., and then 0.27 g of sulfuric anhydridewas added. Then, solution, in which 7.0 g of high-impact polystylene (o)was dissolved in 63 g of 1,2-dichloroethane, and 4.3 g of sulfuricanhydride were simultaneously dropped to the above-mentioned solution in60 minutes in a state where the temperature of the solution wasmaintained at 20° C. to 25° C. Then, the sulfonation was performed forone hour.

Then, sodium hydroxide solution was, while being stirred, graduallyadded-to the above-mentioned reaction system so that the solution wasneutralized. The thus-obtained. polyelectrolyte solution was calledsample water solution according to Example 18.

Example 19

The temperature of solution in which 0.6 g of triethyl phosphate wasadded to 70 g of 1,2-dichloroethane was maintained at 20° C. to 25° C.,and then 0.27 g of sulfuric anhydride was added. Then, solution, inwhich 7.0 g of high-impact polystylene (p) was dissolved in 63 g of1,2-dichloroethane, and 4.3 g of sulfuric anhydride were simultaneouslydropped to the above-mentioned solution in 60 minutes in a state wherethe temperature was maintained at 20° C. to 25° C. Then, sulfonation wasperformed for one hour.

Then, sodium hydroxide solution was, while being stirred, graduallyadded to the above-mentioned reaction system so that the solution wasneutralized. The thus-obtained polyelectrolyte solution was calledsample water solution according to Example 19.

Example 20

A process similar to that according to Example 6 was performed exceptfor the alloy of high-impact polystylene-polyphenyleneether (q) beingemployed as the resin so that sulfonation was performed. Then, thesolution was neutralized. The thus-obtained polyelectrolyte solution wascalled sample water solution according to Example 20.

Example 21

5 g of high-impact polystylene (r) was dissolved in 20 g oftetrachloroethane, and then 45 g of chloroether was added. Then, 15 g ofaluminum chloride was gradually added and stirred for 3 hours at 60° C.After reactions had been completed, the residual chloromethylether wasdistillated under lowered pressure, and then ammonia water having thesame mol as that of the chloromethyl groups introduced into the resin(r) was added. As a result, chloromethylated amine salt was introducedinto the resin (r). The thus-obtained polyelectrolyte solution wascalled sample water solution according to Example 21.

Example 22

As an alternative to addition of carbon black prior to performingsulfonation, 0.5 g of carbon black was added after the sulfonationprocess and the neutralizing process. A process similar to thataccording to Example 18 was performed except for the above-mentionedprocess so that a polyelectrolyte was obtained. The thus-obtainedpolyelectrolyte solution was called sample water solution according toExample 22.

Comparative Example 11

A process similar to that according to Example 19 was performed exceptfor high-impact polystylene (o) being used as the resin so thatsulfonation was performed. Then, the solution was neutralized. Thethus-obtained polyelectrolyte solution was called sample water solutionaccording to Comparative Example 11.

Comparative Example 12

A process similar to that according to Example 21 was performed exceptfor high-impact polystylene (o) being used as the resin so thatchlorometylation was performed. Then, the solution was neutralized. Thethus-obtained polyelectrolyte solution was called sample water solutionaccording to Comparative Example 12.

Evaluation of Characteristics

The long-term stability of each of the sample water solutions accordingto the Examples 18 to 22 and Comparative Examples 11 and 12 wasevaluated.

Specifically, sample water solutions were injected into sample bottlesmade of transparent glass and sample bottles made of light shieldingglass, and then allowed to stand at the room temperature for threemonths. At an interval of one month, the state of each sample watersolution was observed. Results of reservation in the sample bottles madeof transparent glass were shown in Table 5, while results of reservationin the sample bottles made of light shielding glass were shown in Table6.

TABLE 5 After After Two After Three One Month Months Months Example 18no change no change no change Example 19 no change no change no changeExample 20 no change no change no change Example 21 no change no changeno change Example 22 carbon black carbon black carbon black depositeddeposited deposited Comparative gelled gelled gelled Example 11substances substances substances Comparative gelled gelled gelledExample 12 substances substances substances

TABLE 6 After After Two After Three One Month Months Months Example 18no change no change no change Example 19 no change no change no changeExample 20 no change no change no change Example 21 no change no changeno change Example 22 carbon black carbon black carbon black depositeddeposited deposited Comparative no change no change gelled Example 11substances generated partially Comparative no change no change gelledExample 12 substances generated partially

As can be understood from Tables 5 and 6, the sample water solutionsaccording to Comparative Examples 11 and 12 each having no carbon blackcontained therein encountered generation of gelled substances. On theother hand, the sample water solutions according to Examples 18 to 22each containing carbon black were free from generation of gelledsubstances during reservation and thus they have excellent long-termstability.

As can be understood from results of Examples 18 to 21, long-termstability can be obtained by introducing the ion groups into the resin,such as resins (p) to (r), previously containing carbon black or byadding carbon black to the reaction system when the ion groups areintroduced. If carbon black is added to the polyelectrolyte solutioninto which the ion groups have been introduced, deterioration of theresin components in the sample water solution with time can beprevented. Since added carbon black cannot uniformly be dispersed andthe carbon black is deposited in this case, it is preferable that carbonblack be allowed to exist when the ion groups are introduced as isperformed in each of Examples 18 to 21.

As a result, introduction of the ion groups in a state where inorganicpigment exists in the reaction system is able to improve the long-termstability.

Addition of Stabilizer

To prepare polyelectrolyte, the following raw materials were prepared.

<Stabilizer>

(1)triethyleneglycol-bis[3-(3-t-butyl-4-hydroxy-5-methylphenyl)propionate]

(2) dilaurylthiodipropionate

(3)3,9-bis[1,1-dimethyl-2-[β-(3-t-butyl-4-hydroxy-5-methylphehyl)propionyloxy]ethyl]2,4,8,10-tetraoxaspyro[5,5]undecane

(4) tris(2,4-di-t-butylphenyl)phosphite

(5) bis-[2,2,6,6-tetramethyl-4-piperidyl]sebacate

(6) erysorbic acid soda

<Raw Material for Polymer>

(A) polystyrene: reagent

molecular weight Mw: 290,000

stabilizer: not added

(B) high-impact polystylene: waste of housing for VHS cassette tape

molecular weight Mw: 190,000

stabilizer (1)+(2): 0.05 wt %+0.05 wt % (with respect to the weight ofthe resin)

(C) polystyrene-polyphenyleneether alloy: material for housing forCD-ROM driver

polystyrene (molecular weight Mw: 200,000)/polyphenyleneether=1/1(weight ratio)

oxidation preventive material (3)+(4)+(5)=0.1 wt %+0.5 wt %+1 wt % (withrespect to the weight of the resin).

Materials (B) and (C) were obtained by crushing the raw materials by ashredder.

<Water-Soluble Polystyrene Polyelectrolyte>

(D) poly (vinylbenzyl trimethylammomonium chloride) solution: Reagent

molecular weight Mw: 100,000

stabilizer: not added

Note that the molecular weight of each polymer was measured by GPCanalysis.

Example 23

0.02 g of the stabilizer (1) was added to solution in which 0.6 g oftriethyl phosphate was added to 70 g of 1,2-dichloroethane. Then, in astate where the temperature of the solution was maintained at 20° C. to25° C., 0.27 g of sulfuric anhydride was added. Then, solution in which7.0 g of the polymer material (A) was dissolved in 63 g of1,2-dichloroethane and 4.3 g of sulfuric anhydride were simultaneouslydropped in 60 minutes in state where their temperature were made to bethe same. After reactions were performed for one hour, sodium hydroxidesolution was, while being stirred, gradually added to the reactionsystem so that neutralization was performed. As a result of theabove-mentioned process, polystyrene sulfonate soda solution (apolyelectrolyte composition according to Example 23) having molecularweight Mw of 710,000 was obtained.

Example 24

0.17 g of fuming sulfuric acid (containing SO₃ by 60 wt %) was added ina state where the temperature of solution in which 0.92 g of triethylphosphate was added to 50 g of cyclohexane was maintained at 50° C.Then, solution in which 2.4 g of the polymer material (B) whichcontained the stabilizer and which was a waste was dissolved in 120 g ofcyclohexane and 3.3 g of fuming sulfuric acid were simultaneouslydropped in 30 minutes in state where their temperatures were made to bethe same. Then, the temperature was maintained at 50±2° C. and thereactions were performed for one hour. Then, 21 g of water solutioncontaining 2.1 g of sodium hydroxide was gradually added while stirringthe water solution so that neutralization was performed. Then, thesolution was heated so that cyclohexane which was the solvent wasremoved by distillation. As a result of the above-mentioned process, apolyelectrolyte composition having molecular weight Mw of 4,500,000 andaccording to Example 24 was obtained.

Example 25

A process similar to that according to Comparative Example 13 wasperformed except for the polymer material (C) being employed so thatsulfonation was performed. The molecular weight Mw of the obtainedpolystyrene sulfonate soda (a polyelectrolyte composition according toExample 25) was 500,000.

Example 26

The stabilizer (6) was added to 25 wt % water solution (Mw: 100,000) ofthe water-soluble polystyrene polyelectrolyte (D) with respect to 100parts by weight of a polyelectrolyte so that a polyelectrolytecomposition according to Example 26 was obtained.

Comparative Example 13

A similar process to that according to Example 23 was performed exceptfor the stabilizer (1) being omitted so that a sample according toComparative Example 13 was prepared. In this case, polystyrene sulfonatesoda solution (a polyelectrolyte composition according to ComparativeExample 13) having molecular weight Mw of 500,000 was obtained.

Comparative Example 14

A process similar to that according to Example 26 was performed exceptfor the stabilizer (6) being omitted so that a polyelectrolytecomposition according to Comparative Example 14 was obtained.

Examination of Effects

Effects of Examples 23 to 26 and Comparative Examples 13 and 14 wereexamined as follows:

The examination was performed such that samples according to Examples 13to 26 and Comparative Examples 13 and 14 were respectively injected intotransparent glass bottles. To measure deterioration of each sample withtime, the appearance and the molecular weight were measured when thesamples were manufactured, and after six and 12 months. Results wereshown in Table 7.

TABLE 7 when after after Sample manufactured 6 months 12 months Example23 710,000 700,000 700,000 (molecular transparent transparenttransparent weight) (appearance) Example 24 450,000 430,000 430,000(molecular light yellow light yellow light yellow weight) (appearance)Example 25 500,000 490,000 480,000 (molecular light yellow light yellowlight yellow weight) (appearance) Example 26 100,000 98,000 98,000(molecular transparent transparent transparent weight) (appearance)Comparative 500,000 360,000 280,000 Example 13 transparent light yellowlight yellow (molecular weight) (appearance) Comparative 100,000 78,00061,000 Example 14 transparent transparent light yellow (molecularweight) (appearance)

As can be understood from Table 7, the polyelectrolyte compositionsaccording to Comparative Examples 13 and 14 encountered reduction in themolecular weight with time and also the apparatus was changed. On theother hand, the polyelectrolyte compositions according to Examples 23 to26 resulted in that the molecular weight when manufactured wassubstantially the same even after the long time had passed. Appearanceof each of the polyelectrolyte compositions according to Examples 23 to26 was not changed with time.

As can be understood from the above-mentioned results, thepolyelectrolyte composition according to the present invention is ableto prevent reduction in the molecular weight because the stabilizerprevents the decomposition reactions of the Polystyrene polyelectrolyte.Since the stabilizer of the polyelectrolyte according to the presentinvention is able to improve the stability of the polystyrenepolyelectrolyte with time, the appearance can be maintained even afterallowed to stand for a long time. Therefore, the polyelectrolytecomposition according to the present invention is able to maintain thehigh quality of the polystyrene polyelectrolyte for a long time.

When Example 23 and Comparative Example 13 shown in Table 7 arecompared, the molecular weight of Example 23 when manufactured is largerthan that of Comparative Example 13. As a result, addition of thestabilizer when the ion groups are, as is performed in Example 23,introduced into the styrene polymers is able to prevent reduction in themolecular weight when manufactured. That is, as can be understood fromExample 23, the stabilizer is able to inhibit automatic oxidationreactions of the styrene polymers attributable to radicals generatedowning to oxygen in the air, heat, light or metal. Therefore, the methodof manufacturing the polyelectrolyte composition according to thepresent invention is able to prevent reduction in the molecular weightof the polystyrene polyelectrolyte and manufacture a polyelectrolytecomposition containing high grade polystyrene polyelectrolyte.

Also the polyelectrolyte compositions according to Examples 24 and 25using the wastes were free from reduction in the molecular weight andchange in the appearance. Therefore, a fact was confirmed that usualwastes can effectively be used as the raw material for thepolyelectrolyte composition according to the present invention.

Addition of Alicyclic Unsaturated Hydrocarbon

(Sulfonation of Polystyrene Resin)

As the polystyrene resin, the following materials were prepared.

(E) reagent polystyrene having molecular weight Mw of 220,000 (noinorganic pigment added);

(F) waste polystyrene which was polystyrene (containing limonene by 0.2wt %) obtained such that foamable styrol was dissolved in limonene andlimonene was removed by distillation by a heating separator and havingmolecular weight of 220,000 (containing no inorganic pigment addedthereto); and

(G) waste high-impact polystylene which was a waste of a housing for aVHS cassette tape and which had molecular weight Mw of 200,000(containing carbon black by 1 wt %).

Note that polystyrene resin (G) was obtained by crushing the rawmaterial by a shredder.

Comparative Example 15

6.0 g of polystyrene (E) was added to 40 g of 1,2-dichloroethane towhich 2.0 g of triethyl phosphate was added, and then the polystyrenewas dissolved.

Then, 7.7 g of 60% fuming sulfuric acid was dropped in 30 minutes in astate where the temperature of the above-mentioned solution wasmaintained at 30° C. After start of the dropping operation, a largequantity of slurry was generate in the reaction system in about 10minutes. When the dropping operation was ended, the operation of thestirrer (a magnetic stirrer) was stopped attributable to the bulk slurryin the bottom of the reactor.

Then, the solution was matured for one hour. Obtained slurry could notcompletely be dissolved in water or alkaline solution.

Example 27

Sulfonation was performed by the same method as that employed inComparative Example 15 and using the polystyrene waste (B). Slurrydeposited during the reactions was dispersed uniformly and thus thestirrer was able to rotate until the completion of the reactions.

The obtained slurry was completely dissolved in water and alkalinesolution. The molecular weight (Mw) of the obtained polyelectrolyte was460,000.

Comparative Example 16

0.35 g of sulfuric anhydride was added in a state where the temperatureof solution in which 0.3 g of triethyl phosphate was added to 30 g ofcyclohexane was maintained at 50° C.

Then, solution in which 6.0 g of waste high-impact polystylene (G) wasdissolved in 64 g cyclohexane in a hot state of 50° C. and 4.5 g ofsulfuric anhydride were simultaneously dropped in 60 minutes such thattheir temperatures were made to be the same.

Also in this case, slurry was deposited during the dropping operation.When the dropping operation was completed, the operation of the stirrerwas stopped attributable to the bulky slurry in the bottom of thereactor.

Then, the solution was matured in the above-mentioned state for onehour. The obtained slurry was not completely dissolved in water andalkaline solution.

Example 28

A method similar to that according to Comparative Example 16 wasemployed except for 0.05 g of cyclohexene being added to cyclohexane inwhich high-impact polystylene waste (G) so that sulfonation wasperformed.

Slurry deposited during the reactions was dispersed uniformly and thusthe stirrer was able to rotate until the completion of the reactions.

The obtained slurry was completely dissolved in water and alkalinesolution. The molecular weight (Mw) of the obtained polyelectrolyte was400,000.

Example 29

6.0 g of polystyrene (A) was added to 40 g of 1,2-dichloroethane towhich triethyl phosphate was added, and then the polystyrene (A) wasdissolved.

Then, terpinene was added by 0.03 g, and then 7.7 g of 60% fumingsulfuric acid was dropped in 30 minutes in a state where the temperatureof the solution was maintained at 30° C.

Although a large quantity of slurry was generated in the reaction systemabout 10 minutes after start of the dropping operation, the slurry wasdispersed uniformly and thus the stirrer was not stopped.

The obtained slurry was completely dissolved in water and alkalinesolution. The molecular weight (Mw) of the obtained polyelectrolyte was480,000.

Example 30

A method similar to that according to Example 29 was employed except for0.05 g of methylcyclohexane being used in place of terpinene so thatsulfonation was performed.

Also in this case, slurry which was dissolved in water and alkalinesolution was generated and the molecular weight (Mw) of thepolyelectrolyte was 450,0001

As a result of Comparative Example 15 and Example 27, use of thepolystyrene resin previously containing the alicyclic unsaturatedhydrocarbon (limonene) enables sulfonation to be performed at a highconcentration.

Moreover, addition of the alicyclic unsaturated hydrocarbon to thesystem according to Comparative Example 15, sulfonation can be performedat a high concentration as can be performed in Examples 29 and 30.

As can be understood from the results of Comparative Example 16 andExample 28, addition of the alicyclic unsaturated hydrocarbon to thesulfonating reaction system enables sulfonation to stably be performedat a high concentration.

Although the invention has been described in its preferred form with acertain degree of particularity, it is understood that the presentdisclosure of the preferred form can be changed in the details ofconstruction and in the combination and arrangement of parts withoutdeparting from the spirit and the scope of the invention as hereinafterclaimed.

What is claimed is:
 1. A method of manufacturing a polymer electrolytecomprising: dissolving a styrene polymer in a cycloolefin solventselected from the group consisting of a cyclohexene, a monocyclicmonoterepene, and a dicyclic monoterpene; and sulfonating the styrenepolymer in the cycloolefin solvent with a sulfonating agent comprisingat least one of sulfuric anhydride, fuming sulfuric acid, chlorosulfonicacid, and sulfphuric acid.
 2. The method of claim 1 wherein the styrenepolymer contains an inorganic pigment.
 3. The method of claim 2 whereinthe inorganic pigment is selected from the group consisting of carbonblack, titanium oxide and mixtures thereof.
 4. The method of claim 1,wherein the monocyclic monoterepene is selected from the groupconsisting of limonene, sylvestrene, terpinen, and teripinolene.
 5. Themethod of claim 1, wherein the dicyclic monoterpene is selected from thegroup consisting of carene, pinene, sabinene, and camphene.
 6. Themethod of claim 1, wherein the styrene polymer is first dissolved in thecycloolefin solvent to form a solution, and then the sulfonating agentis dropped into the solution.
 7. The method of claim 1, wherein thesulfonating agent is added to the cyclooelefin solvent to form a firstsolution, the styrene polymer is dissolved in the cycloolefin solvent toform a second solution, and then the second solution is dropped into thefirst solution.
 8. A method of manufacturing a polymer electrolytecomprising: dissolving a styrene polymer in a cycloolefin solvent; andsulfonating the styrene polymer in the cycloolefin solvent with asulfonating agent comprising at least one of sulfuric anhydride, fumingsulfuric acid, chlorosulfonic acid, and sulfphuric acid; wherein thecycloolefin solvent is selected from the group consisting of acyclohexene, a monocyclic monoterepene, and a dicyclic monoterpene;wherein the monocyclic monoterepene is selected from the groupconsisting of limonene, sylvestrene, terpinen, and teripinolene; whereinthe dicyclic monoterpene is selected from the group consisting ofcarene, pinene, sabinene, and camphene; and wherein the styrene polymeris first dissolved in the cycloolefin solvent to form a solution, andthen the sulfonating agent is dropped into the solution.
 9. A method ofmanufacturing a polymer electrolyte comprising: dissolving a styrenepolymer in a cycloolefin solvent; and sulfonating the styrene polymer inthe cycloolefin solvent with a sulfonating agent comprising at least oneof sulfuric anhydride, fuming sulfuric acid, chlorosulfonic acid, andsulfphuric acid; wherein the cycloolefin solvent is selected from thegroup consisting of a cyclohexene, a monocyclic monoterepene, and adicyclic monoterpene; wherein the monocyclic monoterepene is selectedfrom the group consisting of limonene, sylvestrene, terpinen, andteripinolene; wherein the dicyclic monoterpene is selected from thegroup consisting of carene, pinene, sabinene, and camphene; and whereinthe sulfonating agent is added to the cyclooelefin solvent to form afirst solution, the styrene polymer is dissolved in the cycloolefinsolvent to form a second solution, and then the second solution isdropped into the first solution.